Release version 0.5.0 (merge into stable)

26 files changed, 992 insertions, 824 deletions

diff --git a/src/main/java/sevenUnits/ProgramInfo.java b/src/main/java/sevenUnits/ProgramInfo.java
index da66b4c..9c23c49 100644
--- a/src/main/java/sevenUnits/ProgramInfo.java
+++ b/src/main/java/sevenUnits/ProgramInfo.java
@@ -1,5 +1,5 @@
 /**
- * Copyright (C) 2021-2023 Adrien Hopkins
+ * Copyright (C) 2021-2024 Adrien Hopkins
  *
  * This program is free software: you can redistribute it and/or modify
  * it under the terms of the GNU Affero General Public License as published by
@@ -25,15 +25,15 @@ import sevenUnits.utils.SemanticVersionNumber;
  * @since 2021-06-28
  */
 public final class ProgramInfo {
-	
-	/** The version number (0.4.1) */
+
+	/** The version number (0.5.0) */
 	public static final SemanticVersionNumber VERSION = SemanticVersionNumber
-			.stableVersion(0, 4, 1);
-	
+			.stableVersion(0, 5, 0);
+
 	private ProgramInfo() {
 		// this class is only for static variables, you shouldn't be able to
 		// construct an instance
 		throw new AssertionError();
 	}
-	
+
 }
diff --git a/src/main/java/sevenUnits/unit/BaseDimension.java b/src/main/java/sevenUnits/unit/BaseDimension.java
index 820d48c..3f1f75f 100644
--- a/src/main/java/sevenUnits/unit/BaseDimension.java
+++ b/src/main/java/sevenUnits/unit/BaseDimension.java
@@ -39,7 +39,7 @@ public final class BaseDimension implements Nameable {
 	public static BaseDimension valueOf(final String name, final String symbol) {
 		return new BaseDimension(name, symbol);
 	}
-	
+
 	/**
 	 * The name of the dimension.
 	 */
@@ -49,7 +49,7 @@ public final class BaseDimension implements Nameable {
 	 * or two characters.
 	 */
 	private final String symbol;
-	
+
 	/**
 	 * Creates the {@code BaseDimension}.
 	 * 
@@ -62,7 +62,7 @@ public final class BaseDimension implements Nameable {
 		this.name = Objects.requireNonNull(name, "name must not be null.");
 		this.symbol = Objects.requireNonNull(symbol, "symbol must not be null.");
 	}
-	
+
 	/**
 	 * @since v0.4.0
 	 */
@@ -70,7 +70,7 @@ public final class BaseDimension implements Nameable {
 	public NameSymbol getNameSymbol() {
 		return NameSymbol.of(this.name, this.symbol);
 	}
-	
+
 	@Override
 	public String toString() {
 		return String.format("%s (%s)", this.name, this.symbol);
diff --git a/src/main/java/sevenUnits/unit/BaseUnit.java b/src/main/java/sevenUnits/unit/BaseUnit.java
index dba7f52..fe85a7b 100644
--- a/src/main/java/sevenUnits/unit/BaseUnit.java
+++ b/src/main/java/sevenUnits/unit/BaseUnit.java
@@ -46,7 +46,7 @@ public final class BaseUnit extends Unit {
 			final String name, final String symbol) {
 		return new BaseUnit(dimension, name, symbol, new HashSet<>());
 	}
-	
+
 	/**
 	 * Gets a base unit from the dimension it measures, its name and its symbol.
 	 * 
@@ -60,12 +60,12 @@ public final class BaseUnit extends Unit {
 			final String name, final String symbol, final Set<String> otherNames) {
 		return new BaseUnit(dimension, name, symbol, otherNames);
 	}
-	
+
 	/**
 	 * The dimension measured by this base unit.
 	 */
 	private final BaseDimension dimension;
-	
+
 	/**
 	 * Creates the {@code BaseUnit}.
 	 * 
@@ -81,7 +81,7 @@ public final class BaseUnit extends Unit {
 		this.dimension = Objects.requireNonNull(dimension,
 				"dimension must not be null.");
 	}
-	
+
 	/**
 	 * Returns a {@code LinearUnit} with this unit as a base and a conversion
 	 * factor of 1. This operation must be done in order to allow units to be
@@ -93,17 +93,17 @@ public final class BaseUnit extends Unit {
 	public LinearUnit asLinearUnit() {
 		return LinearUnit.valueOf(this.getBase(), 1);
 	}
-	
+
 	@Override
 	protected double convertFromBase(final double value) {
 		return value;
 	}
-	
+
 	@Override
 	protected double convertToBase(final double value) {
 		return value;
 	}
-	
+
 	/**
 	 * @return dimension
 	 * @since 2019-10-16
@@ -111,7 +111,7 @@ public final class BaseUnit extends Unit {
 	public final BaseDimension getBaseDimension() {
 		return this.dimension;
 	}
-	
+
 	@Override
 	public String toString() {
 		return this.getPrimaryName().orElse("Unnamed unit")
@@ -119,7 +119,7 @@ public final class BaseUnit extends Unit {
 						? String.format(" (%s)", this.getSymbol().get())
 						: "");
 	}
-	
+
 	@Override
 	public BaseUnit withName(final NameSymbol ns) {
 		Objects.requireNonNull(ns, "ns must not be null.");
diff --git a/src/main/java/sevenUnits/unit/BritishImperial.java b/src/main/java/sevenUnits/unit/BritishImperial.java
index 0ecba6d..69a3c05 100644
--- a/src/main/java/sevenUnits/unit/BritishImperial.java
+++ b/src/main/java/sevenUnits/unit/BritishImperial.java
@@ -39,7 +39,7 @@ public final class BritishImperial {
 		public static final LinearUnit ROOD = Length.ROD.times(Length.FURLONG);
 		public static final LinearUnit ACRE = Length.FURLONG.times(Length.CHAIN);
 	}
-	
+
 	/**
 	 * Imperial units that measure length
 	 * 
@@ -59,15 +59,15 @@ public final class BritishImperial {
 		public static final LinearUnit FURLONG = CHAIN.times(10);
 		public static final LinearUnit MILE = FURLONG.times(8);
 		public static final LinearUnit LEAGUE = MILE.times(3);
-		
+
 		public static final LinearUnit NAUTICAL_MILE = Metric.METRE.times(1852);
 		public static final LinearUnit CABLE = NAUTICAL_MILE.dividedBy(10);
 		public static final LinearUnit FATHOM = CABLE.dividedBy(100);
-		
+
 		public static final LinearUnit ROD = YARD.times(5.5);
 		public static final LinearUnit LINK = ROD.dividedBy(25);
 	}
-	
+
 	/**
 	 * British Imperial units that measure mass.
 	 * 
@@ -85,7 +85,7 @@ public final class BritishImperial {
 		public static final LinearUnit LONG_TON = HUNDREDWEIGHT.times(20);
 		public static final LinearUnit SLUG = Metric.KILOGRAM.times(14.59390294);
 	}
-	
+
 	/**
 	 * British Imperial units that measure volume
 	 * 
@@ -101,23 +101,23 @@ public final class BritishImperial {
 		public static final LinearUnit GALLON = QUART.times(4);
 		public static final LinearUnit PECK = GALLON.times(2);
 		public static final LinearUnit BUSHEL = PECK.times(4);
-		
+
 		public static final LinearUnit CUBIC_INCH = Length.INCH.toExponent(3);
 		public static final LinearUnit CUBIC_FOOT = Length.FOOT.toExponent(3);
 		public static final LinearUnit CUBIC_YARD = Length.YARD.toExponent(3);
 		public static final LinearUnit ACRE_FOOT = Area.ACRE.times(Length.FOOT);
 	}
-	
+
 	public static final LinearUnit OUNCE_FORCE = Mass.OUNCE
 			.times(Metric.Constants.EARTH_GRAVITY);
 	public static final LinearUnit POUND_FORCE = Mass.POUND
 			.times(Metric.Constants.EARTH_GRAVITY);
-	
+
 	public static final LinearUnit BRITISH_THERMAL_UNIT = Metric.JOULE
 			.times(1055.06);
 	public static final LinearUnit CALORIE = Metric.JOULE.times(4.184);
 	public static final LinearUnit KILOCALORIE = Metric.JOULE.times(4184);
-	
+
 	public static final Unit FAHRENHEIT = Unit
 			.fromConversionFunctions(Metric.KELVIN.getBase(),
 					tempK -> tempK * 1.8 - 459.67, tempF -> (tempF + 459.67) / 1.8)
diff --git a/src/main/java/sevenUnits/unit/FunctionalUnit.java b/src/main/java/sevenUnits/unit/FunctionalUnit.java
index 720b0af..6de446f 100644
--- a/src/main/java/sevenUnits/unit/FunctionalUnit.java
+++ b/src/main/java/sevenUnits/unit/FunctionalUnit.java
@@ -30,14 +30,16 @@ import sevenUnits.utils.ObjectProduct;
  */
 final class FunctionalUnit extends Unit {
 	/**
-	 * A function that accepts a value expressed in the unit's base and returns that value expressed in this unit.
+	 * A function that accepts a value expressed in the unit's base and returns
+	 * that value expressed in this unit.
 	 * 
 	 * @since 2019-05-22
 	 */
 	private final DoubleUnaryOperator converterFrom;
 
 	/**
-	 * A function that accepts a value expressed in the unit and returns that value expressed in the unit's base.
+	 * A function that accepts a value expressed in the unit and returns that
+	 * value expressed in the unit's base.
 	 * 
 	 * @since 2019-05-22
 	 */
@@ -46,45 +48,43 @@ final class FunctionalUnit extends Unit {
 	/**
 	 * Creates the {@code FunctionalUnit}.
 	 * 
-	 * @param base
-	 *            unit's base
-	 * @param converterFrom
-	 *            function that accepts a value expressed in the unit's base and returns that value expressed in this
-	 *            unit.
-	 * @param converterTo
-	 *            function that accepts a value expressed in the unit and returns that value expressed in the unit's
-	 *            base.
-	 * @throws NullPointerException
-	 *             if any argument is null
+	 * @param base          unit's base
+	 * @param converterFrom function that accepts a value expressed in the unit's
+	 *                      base and returns that value expressed in this unit.
+	 * @param converterTo   function that accepts a value expressed in the unit
+	 *                      and returns that value expressed in the unit's base.
+	 * @throws NullPointerException if any argument is null
 	 * @since 2019-05-22
 	 */
-	public FunctionalUnit(final ObjectProduct<BaseUnit> base, final DoubleUnaryOperator converterFrom,
+	public FunctionalUnit(final ObjectProduct<BaseUnit> base,
+			final DoubleUnaryOperator converterFrom,
 			final DoubleUnaryOperator converterTo) {
 		super(base, NameSymbol.EMPTY);
-		this.converterFrom = Objects.requireNonNull(converterFrom, "converterFrom must not be null.");
-		this.converterTo = Objects.requireNonNull(converterTo, "converterTo must not be null.");
+		this.converterFrom = Objects.requireNonNull(converterFrom,
+				"converterFrom must not be null.");
+		this.converterTo = Objects.requireNonNull(converterTo,
+				"converterTo must not be null.");
 	}
 
 	/**
 	 * Creates the {@code FunctionalUnit}.
 	 * 
-	 * @param base
-	 *            unit's base
-	 * @param converterFrom
-	 *            function that accepts a value expressed in the unit's base and returns that value expressed in this
-	 *            unit.
-	 * @param converterTo
-	 *            function that accepts a value expressed in the unit and returns that value expressed in the unit's
-	 *            base.
-	 * @throws NullPointerException
-	 *             if any argument is null
+	 * @param base          unit's base
+	 * @param converterFrom function that accepts a value expressed in the unit's
+	 *                      base and returns that value expressed in this unit.
+	 * @param converterTo   function that accepts a value expressed in the unit
+	 *                      and returns that value expressed in the unit's base.
+	 * @throws NullPointerException if any argument is null
 	 * @since 2019-05-22
 	 */
-	public FunctionalUnit(final ObjectProduct<BaseUnit> base, final DoubleUnaryOperator converterFrom,
+	public FunctionalUnit(final ObjectProduct<BaseUnit> base,
+			final DoubleUnaryOperator converterFrom,
 			final DoubleUnaryOperator converterTo, final NameSymbol ns) {
 		super(base, ns);
-		this.converterFrom = Objects.requireNonNull(converterFrom, "converterFrom must not be null.");
-		this.converterTo = Objects.requireNonNull(converterTo, "converterTo must not be null.");
+		this.converterFrom = Objects.requireNonNull(converterFrom,
+				"converterFrom must not be null.");
+		this.converterTo = Objects.requireNonNull(converterTo,
+				"converterTo must not be null.");
 	}
 
 	/**
diff --git a/src/main/java/sevenUnits/unit/FunctionalUnitlike.java b/src/main/java/sevenUnits/unit/FunctionalUnitlike.java
index d6046c0..e9b4d1f 100644
--- a/src/main/java/sevenUnits/unit/FunctionalUnitlike.java
+++ b/src/main/java/sevenUnits/unit/FunctionalUnitlike.java
@@ -35,13 +35,13 @@ final class FunctionalUnitlike<V> extends Unitlike<V> {
 	 * @since 2020-09-07
 	 */
 	private final DoubleFunction<V> converterFrom;
-	
+
 	/**
 	 * A function that accepts a value in the unitlike form and returns a value
 	 * in the unitlike form's base.
 	 */
 	private final ToDoubleFunction<V> converterTo;
-	
+
 	/**
 	 * Creates the {@code FunctionalUnitlike}.
 	 * 
@@ -59,15 +59,15 @@ final class FunctionalUnitlike<V> extends Unitlike<V> {
 		this.converterFrom = converterFrom;
 		this.converterTo = converterTo;
 	}
-	
+
 	@Override
 	protected V convertFromBase(double value) {
 		return this.converterFrom.apply(value);
 	}
-	
+
 	@Override
 	protected double convertToBase(V value) {
 		return this.converterTo.applyAsDouble(value);
 	}
-	
+
 }
diff --git a/src/main/java/sevenUnits/unit/LinearUnit.java b/src/main/java/sevenUnits/unit/LinearUnit.java
index 103b7f6..6489229 100644
--- a/src/main/java/sevenUnits/unit/LinearUnit.java
+++ b/src/main/java/sevenUnits/unit/LinearUnit.java
@@ -46,7 +46,7 @@ public final class LinearUnit extends Unit {
 				Objects.requireNonNull(unit, "unit must not be null.").getBase(),
 				unit.convertToBase(value), NameSymbol.EMPTY);
 	}
-	
+
 	/**
 	 * Gets a {@code LinearUnit} from a unit and a value. For example, converts
 	 * '59 °F' to a linear unit with the value of '288.15 K'
@@ -64,7 +64,7 @@ public final class LinearUnit extends Unit {
 				Objects.requireNonNull(unit, "unit must not be null.").getBase(),
 				unit.convertToBase(value), ns);
 	}
-	
+
 	/**
 	 * @return the base unit associated with {@code unit}, as a
 	 *         {@code LinearUnit}.
@@ -73,7 +73,7 @@ public final class LinearUnit extends Unit {
 	public static LinearUnit getBase(final Unit unit) {
 		return new LinearUnit(unit.getBase(), 1, NameSymbol.EMPTY);
 	}
-	
+
 	/**
 	 * @return the base unit associated with {@code unitlike}, as a
 	 *         {@code LinearUnit}.
@@ -82,7 +82,7 @@ public final class LinearUnit extends Unit {
 	public static LinearUnit getBase(final Unitlike<?> unit) {
 		return new LinearUnit(unit.getBase(), 1, NameSymbol.EMPTY);
 	}
-	
+
 	/**
 	 * Gets a {@code LinearUnit} from a unit base and a conversion factor. In
 	 * other words, gets the product of {@code unitBase} and
@@ -98,7 +98,7 @@ public final class LinearUnit extends Unit {
 			final double conversionFactor) {
 		return new LinearUnit(unitBase, conversionFactor, NameSymbol.EMPTY);
 	}
-	
+
 	/**
 	 * Gets a {@code LinearUnit} from a unit base and a conversion factor. In
 	 * other words, gets the product of {@code unitBase} and
@@ -115,7 +115,7 @@ public final class LinearUnit extends Unit {
 			final double conversionFactor, final NameSymbol ns) {
 		return new LinearUnit(unitBase, conversionFactor, ns);
 	}
-	
+
 	/**
 	 * The value of this unit as represented in its base form. Mathematically,
 	 * 
@@ -126,7 +126,7 @@ public final class LinearUnit extends Unit {
 	 * @since 2019-10-16
 	 */
 	private final double conversionFactor;
-	
+
 	/**
 	 * Creates the {@code LinearUnit}.
 	 * 
@@ -139,7 +139,7 @@ public final class LinearUnit extends Unit {
 		super(unitBase, ns);
 		this.conversionFactor = conversionFactor;
 	}
-	
+
 	/**
 	 * {@inheritDoc}
 	 * 
@@ -149,7 +149,7 @@ public final class LinearUnit extends Unit {
 	protected double convertFromBase(final double value) {
 		return value / this.getConversionFactor();
 	}
-	
+
 	/**
 	 * Converts an {@code UncertainDouble} value expressed in this unit to an
 	 * {@code UncertainValue} value expressed in {@code other}.
@@ -172,9 +172,9 @@ public final class LinearUnit extends Unit {
 		else
 			throw new IllegalArgumentException(
 					String.format("Cannot convert from %s to %s.", this, other));
-		
+
 	}
-	
+
 	/**
 	 * {@inheritDoc}
 	 * 
@@ -184,7 +184,7 @@ public final class LinearUnit extends Unit {
 	protected double convertToBase(final double value) {
 		return value * this.getConversionFactor();
 	}
-	
+
 	/**
 	 * Converts an {@code UncertainDouble} to the base unit.
 	 * 
@@ -193,7 +193,7 @@ public final class LinearUnit extends Unit {
 	UncertainDouble convertToBase(final UncertainDouble value) {
 		return value.timesExact(this.getConversionFactor());
 	}
-	
+
 	/**
 	 * Divides this unit by a scalar.
 	 * 
@@ -205,7 +205,7 @@ public final class LinearUnit extends Unit {
 	public LinearUnit dividedBy(final double divisor) {
 		return valueOf(this.getBase(), this.getConversionFactor() / divisor);
 	}
-	
+
 	/**
 	 * Returns the quotient of this unit and another.
 	 * 
@@ -217,14 +217,14 @@ public final class LinearUnit extends Unit {
 	 */
 	public LinearUnit dividedBy(final LinearUnit divisor) {
 		Objects.requireNonNull(divisor, "other must not be null");
-		
+
 		// divide the units
 		final ObjectProduct<BaseUnit> base = this.getBase()
 				.dividedBy(divisor.getBase());
 		return valueOf(base,
 				this.getConversionFactor() / divisor.getConversionFactor());
 	}
-	
+
 	/**
 	 * {@inheritDoc}
 	 * 
@@ -239,7 +239,7 @@ public final class LinearUnit extends Unit {
 				&& DecimalComparison.equals(this.getConversionFactor(),
 						other.getConversionFactor());
 	}
-	
+
 	/**
 	 * @return conversion factor
 	 * @since 2019-10-16
@@ -247,7 +247,7 @@ public final class LinearUnit extends Unit {
 	public double getConversionFactor() {
 		return this.conversionFactor;
 	}
-	
+
 	/**
 	 * {@inheritDoc}
 	 * 
@@ -258,7 +258,7 @@ public final class LinearUnit extends Unit {
 		return 31 * this.getBase().hashCode()
 				+ DecimalComparison.hash(this.getConversionFactor());
 	}
-	
+
 	/**
 	 * @return whether this unit is equivalent to a {@code BaseUnit} (i.e. there
 	 *         is a {@code BaseUnit b} where
@@ -268,7 +268,7 @@ public final class LinearUnit extends Unit {
 	public boolean isBase() {
 		return this.isCoherent() && this.getBase().isSingleObject();
 	}
-	
+
 	/**
 	 * @return whether this unit is coherent (i.e. has conversion factor 1)
 	 * @since 2019-10-16
@@ -276,7 +276,7 @@ public final class LinearUnit extends Unit {
 	public boolean isCoherent() {
 		return this.getConversionFactor() == 1;
 	}
-	
+
 	/**
 	 * Returns the difference of this unit and another.
 	 * <p>
@@ -296,18 +296,18 @@ public final class LinearUnit extends Unit {
 	 */
 	public LinearUnit minus(final LinearUnit subtrahend) {
 		Objects.requireNonNull(subtrahend, "addend must not be null.");
-		
+
 		// reject subtrahends that cannot be added to this unit
 		if (!this.getBase().equals(subtrahend.getBase()))
 			throw new IllegalArgumentException(String.format(
 					"Incompatible units for subtraction \"%s\" and \"%s\".", this,
 					subtrahend));
-		
+
 		// subtract the units
 		return valueOf(this.getBase(),
 				this.getConversionFactor() - subtrahend.getConversionFactor());
 	}
-	
+
 	/**
 	 * Returns the sum of this unit and another.
 	 * <p>
@@ -327,18 +327,18 @@ public final class LinearUnit extends Unit {
 	 */
 	public LinearUnit plus(final LinearUnit addend) {
 		Objects.requireNonNull(addend, "addend must not be null.");
-		
+
 		// reject addends that cannot be added to this unit
 		if (!this.getBase().equals(addend.getBase()))
 			throw new IllegalArgumentException(String.format(
 					"Incompatible units for addition \"%s\" and \"%s\".", this,
 					addend));
-		
+
 		// add the units
 		return valueOf(this.getBase(),
 				this.getConversionFactor() + addend.getConversionFactor());
 	}
-	
+
 	/**
 	 * Multiplies this unit by a scalar.
 	 * 
@@ -350,7 +350,7 @@ public final class LinearUnit extends Unit {
 	public LinearUnit times(final double multiplier) {
 		return valueOf(this.getBase(), this.getConversionFactor() * multiplier);
 	}
-	
+
 	/**
 	 * Returns the product of this unit and another.
 	 * 
@@ -362,21 +362,21 @@ public final class LinearUnit extends Unit {
 	 */
 	public LinearUnit times(final LinearUnit multiplier) {
 		Objects.requireNonNull(multiplier, "other must not be null");
-		
+
 		// multiply the units
 		final ObjectProduct<BaseUnit> base = this.getBase()
 				.times(multiplier.getBase());
 		return valueOf(base,
 				this.getConversionFactor() * multiplier.getConversionFactor());
 	}
-	
+
 	@Override
 	public String toDefinitionString() {
 		return Double.toString(this.conversionFactor)
 				+ (this.getBase().equals(ObjectProduct.empty()) ? ""
 						: " " + this.getBase().toString(BaseUnit::getShortName));
 	}
-	
+
 	/**
 	 * Returns this unit but to an exponent.
 	 * 
@@ -389,12 +389,12 @@ public final class LinearUnit extends Unit {
 		return valueOf(this.getBase().toExponent(exponent),
 				Math.pow(this.conversionFactor, exponent));
 	}
-	
+
 	@Override
 	public LinearUnit withName(final NameSymbol ns) {
 		return valueOf(this.getBase(), this.getConversionFactor(), ns);
 	}
-	
+
 	/**
 	 * Returns the result of applying {@code prefix} to this unit.
 	 * <p>
@@ -413,7 +413,7 @@ public final class LinearUnit extends Unit {
 	 */
 	public LinearUnit withPrefix(final UnitPrefix prefix) {
 		final LinearUnit unit = this.times(prefix.getMultiplier());
-		
+
 		// create new name and symbol, if possible
 		final String name;
 		if (this.getPrimaryName().isPresent()
@@ -422,14 +422,14 @@ public final class LinearUnit extends Unit {
 		} else {
 			name = null;
 		}
-		
+
 		final String symbol;
 		if (this.getSymbol().isPresent() && prefix.getSymbol().isPresent()) {
 			symbol = prefix.getSymbol().get() + this.getSymbol().get();
 		} else {
 			symbol = null;
 		}
-		
+
 		return unit.withName(NameSymbol.ofNullable(name, symbol));
 	}
 }
diff --git a/src/main/java/sevenUnits/unit/LinearUnitValue.java b/src/main/java/sevenUnits/unit/LinearUnitValue.java
index f91d30b..3a9428b 100644
--- a/src/main/java/sevenUnits/unit/LinearUnitValue.java
+++ b/src/main/java/sevenUnits/unit/LinearUnitValue.java
@@ -34,7 +34,7 @@ import sevenUnits.utils.UncertainDouble;
  */
 public final class LinearUnitValue {
 	public static final LinearUnitValue ONE = getExact(Metric.ONE, 1);
-	
+
 	/**
 	 * Gets an exact {@code LinearUnitValue}
 	 * 
@@ -49,7 +49,7 @@ public final class LinearUnitValue {
 				Objects.requireNonNull(unit, "unit must not be null"),
 				UncertainDouble.of(value, 0));
 	}
-	
+
 	/**
 	 * Gets an uncertain {@code LinearUnitValue}
 	 * 
@@ -65,11 +65,11 @@ public final class LinearUnitValue {
 				Objects.requireNonNull(unit, "unit must not be null"),
 				Objects.requireNonNull(value, "value may not be null"));
 	}
-	
+
 	private final LinearUnit unit;
-	
+
 	private final UncertainDouble value;
-	
+
 	/**
 	 * @param unit  unit to express as
 	 * @param value value to express
@@ -79,7 +79,7 @@ public final class LinearUnitValue {
 		this.unit = unit;
 		this.value = value;
 	}
-	
+
 	/**
 	 * @return this value as a {@code UnitValue}. All uncertainty information is
 	 *         removed from the returned value.
@@ -88,7 +88,7 @@ public final class LinearUnitValue {
 	public final UnitValue asUnitValue() {
 		return UnitValue.of(this.unit, this.value.value());
 	}
-	
+
 	/**
 	 * @param other a {@code LinearUnit}
 	 * @return true iff this value can be represented with {@code other}.
@@ -97,7 +97,7 @@ public final class LinearUnitValue {
 	public final boolean canConvertTo(final LinearUnit other) {
 		return this.unit.canConvertTo(other);
 	}
-	
+
 	/**
 	 * Returns a LinearUnitValue that represents the same value expressed in a
 	 * different unit
@@ -109,7 +109,7 @@ public final class LinearUnitValue {
 	public final LinearUnitValue convertTo(final LinearUnit other) {
 		return LinearUnitValue.of(other, this.unit.convertTo(other, this.value));
 	}
-	
+
 	/**
 	 * Divides this value by a scalar
 	 * 
@@ -120,7 +120,7 @@ public final class LinearUnitValue {
 	public LinearUnitValue dividedBy(final double divisor) {
 		return LinearUnitValue.of(this.unit, this.value.dividedByExact(divisor));
 	}
-	
+
 	/**
 	 * Divides this value by another value
 	 * 
@@ -132,7 +132,7 @@ public final class LinearUnitValue {
 		return LinearUnitValue.of(this.unit.dividedBy(divisor.unit),
 				this.value.dividedBy(divisor.value));
 	}
-	
+
 	/**
 	 * Returns true if this and obj represent the same value, regardless of
 	 * whether or not they are expressed in the same unit. So (1000 m).equals(1
@@ -150,7 +150,7 @@ public final class LinearUnitValue {
 				&& this.unit.convertToBase(this.value)
 						.equals(other.unit.convertToBase(other.value));
 	}
-	
+
 	/**
 	 * Returns true if this and obj represent the same value, regardless of
 	 * whether or not they are expressed in the same unit. So (1000 m).equals(1
@@ -171,7 +171,7 @@ public final class LinearUnitValue {
 				&& DecimalComparison.equals(this.unit.convertToBase(this.value),
 						other.unit.convertToBase(other.value));
 	}
-	
+
 	/**
 	 * @param other another {@code LinearUnitValue}
 	 * @return true iff this and other are within each other's uncertainty range
@@ -185,10 +185,10 @@ public final class LinearUnitValue {
 		final LinearUnit base = LinearUnit.valueOf(this.unit.getBase(), 1);
 		final LinearUnitValue thisBase = this.convertTo(base);
 		final LinearUnitValue otherBase = other.convertTo(base);
-		
+
 		return thisBase.value.equivalent(otherBase.value);
 	}
-	
+
 	/**
 	 * @return the unit
 	 * @since 2020-09-29
@@ -196,7 +196,7 @@ public final class LinearUnitValue {
 	public final LinearUnit getUnit() {
 		return this.unit;
 	}
-	
+
 	/**
 	 * @return the value
 	 * @since 2020-09-29
@@ -204,7 +204,7 @@ public final class LinearUnitValue {
 	public final UncertainDouble getValue() {
 		return this.value;
 	}
-	
+
 	/**
 	 * @return the exact value
 	 * @since 2020-09-07
@@ -212,13 +212,13 @@ public final class LinearUnitValue {
 	public final double getValueExact() {
 		return this.value.value();
 	}
-	
+
 	@Override
 	public int hashCode() {
 		return Objects.hash(this.unit.getBase(),
 				this.unit.convertToBase(this.getValue()));
 	}
-	
+
 	/**
 	 * Returns the difference of this value and another, expressed in this
 	 * value's unit
@@ -231,17 +231,17 @@ public final class LinearUnitValue {
 	 */
 	public LinearUnitValue minus(final LinearUnitValue subtrahend) {
 		Objects.requireNonNull(subtrahend, "subtrahend may not be null");
-		
+
 		if (!this.canConvertTo(subtrahend.unit))
 			throw new IllegalArgumentException(String.format(
 					"Incompatible units for subtraction \"%s\" and \"%s\".",
 					this.unit, subtrahend.unit));
-		
+
 		final LinearUnitValue otherConverted = subtrahend.convertTo(this.unit);
 		return LinearUnitValue.of(this.unit,
 				this.value.minus(otherConverted.value));
 	}
-	
+
 	/**
 	 * Returns the sum of this value and another, expressed in this value's unit
 	 * 
@@ -253,17 +253,17 @@ public final class LinearUnitValue {
 	 */
 	public LinearUnitValue plus(final LinearUnitValue addend) {
 		Objects.requireNonNull(addend, "addend may not be null");
-		
+
 		if (!this.canConvertTo(addend.unit))
 			throw new IllegalArgumentException(String.format(
 					"Incompatible units for addition \"%s\" and \"%s\".", this.unit,
 					addend.unit));
-		
+
 		final LinearUnitValue otherConverted = addend.convertTo(this.unit);
 		return LinearUnitValue.of(this.unit,
 				this.value.plus(otherConverted.value));
 	}
-	
+
 	/**
 	 * Multiplies this value by a scalar
 	 * 
@@ -274,7 +274,7 @@ public final class LinearUnitValue {
 	public LinearUnitValue times(final double multiplier) {
 		return LinearUnitValue.of(this.unit, this.value.timesExact(multiplier));
 	}
-	
+
 	/**
 	 * Multiplies this value by another value
 	 * 
@@ -286,7 +286,7 @@ public final class LinearUnitValue {
 		return LinearUnitValue.of(this.unit.times(multiplier.unit),
 				this.value.times(multiplier.value));
 	}
-	
+
 	/**
 	 * Raises a value to an exponent
 	 * 
@@ -298,18 +298,18 @@ public final class LinearUnitValue {
 		return LinearUnitValue.of(this.unit.toExponent(exponent),
 				this.value.toExponentExact(exponent));
 	}
-	
+
 	@Override
 	public String toString() {
 		return this.toString(!this.value.isExact(), RoundingMode.HALF_EVEN);
 	}
-	
+
 	/**
 	 * Returns a string representing the object. <br>
 	 * If the attached unit has a name or symbol, the string looks like "12 km".
 	 * Otherwise, it looks like "13 unnamed unit (= 2 m/s)".
 	 * <p>
-	 * If showUncertainty is true, strings like "35 ± 8" are shown instead of
+	 * If showUncertainty is true, strings like "35 � 8" are shown instead of
 	 * single numbers.
 	 * <p>
 	 * Non-exact values are rounded intelligently based on their uncertainty.
@@ -321,9 +321,9 @@ public final class LinearUnitValue {
 		final Optional<String> primaryName = this.unit.getPrimaryName();
 		final Optional<String> symbol = this.unit.getSymbol();
 		final String chosenName = symbol.orElse(primaryName.orElse(null));
-		
+
 		final UncertainDouble baseValue = this.unit.convertToBase(this.value);
-		
+
 		// get rounded strings
 		// if showUncertainty is true, add brackets around the string
 		final String valueString = (showUncertainty ? "(" : "")
@@ -332,7 +332,7 @@ public final class LinearUnitValue {
 		final String baseValueString = (showUncertainty ? "(" : "")
 				+ baseValue.toString(showUncertainty, roundingMode)
 				+ (showUncertainty ? ")" : "");
-		
+
 		// create string
 		if (chosenName == null)
 			return String.format("%s unnamed unit (= %s %s)", valueString,
diff --git a/src/main/java/sevenUnits/unit/Metric.java b/src/main/java/sevenUnits/unit/Metric.java
index 05e82ba..7841987 100644
--- a/src/main/java/sevenUnits/unit/Metric.java
+++ b/src/main/java/sevenUnits/unit/Metric.java
@@ -59,13 +59,13 @@ public final class Metric {
 				.valueOf("Information", "Info"); // non-SI
 		public static final BaseDimension CURRENCY = BaseDimension
 				.valueOf("Currency", "$$"); // non-SI
-		
+
 		// You may NOT get SI.BaseDimensions instances!
 		private BaseDimensions() {
 			throw new AssertionError();
 		}
 	}
-	
+
 	/// base units of the SI
 	// suppressing warnings since these are the same object, but in a different
 	/// form (class)
@@ -89,16 +89,16 @@ public final class Metric {
 				.valueOf(BaseDimensions.INFORMATION, "bit", "b");
 		public static final BaseUnit DOLLAR = BaseUnit
 				.valueOf(BaseDimensions.CURRENCY, "dollar", "$");
-		
+
 		public static final Set<BaseUnit> BASE_UNITS = Set.of(METRE, KILOGRAM,
 				SECOND, AMPERE, KELVIN, MOLE, CANDELA, BIT);
-		
+
 		// You may NOT get SI.BaseUnits instances!
 		private BaseUnits() {
 			throw new AssertionError();
 		}
 	}
-	
+
 	/**
 	 * Constants that relate to the SI or other systems.
 	 * 
@@ -109,7 +109,7 @@ public final class Metric {
 		public static final LinearUnit EARTH_GRAVITY = METRE.dividedBy(SECOND)
 				.dividedBy(SECOND).times(9.80665);
 	}
-	
+
 	// dimensions used in the SI, as ObjectProducts
 	public static final class Dimensions {
 		public static final ObjectProduct<BaseDimension> EMPTY = ObjectProduct
@@ -139,7 +139,7 @@ public final class Metric {
 		public static final ObjectProduct<BaseDimension> CURRENCY = ObjectProduct
 				.oneOf(BaseDimensions.CURRENCY)
 				.withName(NameSymbol.ofName("Currency"));
-		
+
 		// derived dimensions without named SI units
 		public static final ObjectProduct<BaseDimension> AREA = LENGTH
 				.times(LENGTH);
@@ -175,7 +175,7 @@ public final class Metric {
 				.dividedBy(LENGTH);
 		public static final ObjectProduct<BaseDimension> SOLID_ANGLE = AREA
 				.dividedBy(AREA);
-		
+
 		// derived dimensions with named SI units
 		public static final ObjectProduct<BaseDimension> FREQUENCY = EMPTY
 				.dividedBy(TIME);
@@ -209,17 +209,17 @@ public final class Metric {
 				.dividedBy(MASS);
 		public static final ObjectProduct<BaseDimension> CATALYTIC_ACTIVITY = QUANTITY
 				.dividedBy(TIME);
-		
+
 		// You may NOT get SI.Dimension instances!
 		private Dimensions() {
 			throw new AssertionError();
 		}
 	}
-	
+
 	/// The units of the SI
 	public static final LinearUnit ONE = LinearUnit
 			.valueOf(ObjectProduct.empty(), 1);
-	
+
 	public static final LinearUnit METRE = BaseUnits.METRE.asLinearUnit()
 			.withName(NameSymbol.of("metre", "m", "meter"));
 	public static final LinearUnit KILOGRAM = BaseUnits.KILOGRAM.asLinearUnit()
@@ -241,7 +241,7 @@ public final class Metric {
 	// Non-base units
 	public static final LinearUnit RADIAN = METRE.dividedBy(METRE)
 			.withName(NameSymbol.of("radian", "rad"));
-	
+
 	public static final LinearUnit STERADIAN = RADIAN.times(RADIAN)
 			.withName(NameSymbol.of("steradian", "sr"));
 	public static final LinearUnit HERTZ = ONE.dividedBy(SECOND)
@@ -290,7 +290,7 @@ public final class Metric {
 	// common derived units included for convenience
 	public static final LinearUnit GRAM = KILOGRAM.dividedBy(1000)
 			.withName(NameSymbol.of("gram", "g"));
-	
+
 	public static final LinearUnit SQUARE_METRE = METRE.toExponent(2)
 			.withName(NameSymbol.of("square metre", "m^2", "square meter",
 					"metre squared", "meter squared"));
@@ -305,7 +305,7 @@ public final class Metric {
 			.fromConversionFunctions(KELVIN.getBase(), tempK -> tempK - 273.15,
 					tempC -> tempC + 273.15)
 			.withName(NameSymbol.of("degree Celsius", "\u00B0C"));
-	
+
 	public static final LinearUnit MINUTE = SECOND.times(60)
 			.withName(NameSymbol.of("minute", "min"));
 	public static final LinearUnit HOUR = MINUTE.times(60)
@@ -349,7 +349,7 @@ public final class Metric {
 			.fromConversionFunctions(ONE.getBase(), pr -> 10 * Math.log10(pr),
 					dB -> Math.pow(10, dB / 10))
 			.withName(NameSymbol.of("decibel", "dB"));
-	
+
 	/// The prefixes of the SI
 	// expanding decimal prefixes
 	public static final UnitPrefix KILO = UnitPrefix.valueOf(1e3)
@@ -368,7 +368,7 @@ public final class Metric {
 			.withName(NameSymbol.of("zetta", "Z"));
 	public static final UnitPrefix YOTTA = UnitPrefix.valueOf(1e24)
 			.withName(NameSymbol.of("yotta", "Y"));
-	
+
 	// contracting decimal prefixes
 	public static final UnitPrefix MILLI = UnitPrefix.valueOf(1e-3)
 			.withName(NameSymbol.of("milli", "m"));
@@ -386,7 +386,7 @@ public final class Metric {
 			.withName(NameSymbol.of("zepto", "z"));
 	public static final UnitPrefix YOCTO = UnitPrefix.valueOf(1e-24)
 			.withName(NameSymbol.of("yocto", "y"));
-	
+
 	// prefixes that don't match the pattern of thousands
 	public static final UnitPrefix DEKA = UnitPrefix.valueOf(1e1)
 			.withName(NameSymbol.of("deka", "da", "deca", "D"));
@@ -408,7 +408,7 @@ public final class Metric {
 			.withName(NameSymbol.of("pebi", "Pi"));
 	public static final UnitPrefix EXBI = PEBI.times(1024)
 			.withName(NameSymbol.of("exbi", "Ei"));
-	
+
 	// a few prefixed units
 	public static final LinearUnit MICROMETRE = Metric.METRE
 			.withPrefix(Metric.MICRO);
@@ -418,7 +418,7 @@ public final class Metric {
 			.withPrefix(Metric.KILO);
 	public static final LinearUnit MEGAMETRE = Metric.METRE
 			.withPrefix(Metric.MEGA);
-	
+
 	public static final LinearUnit MICROLITRE = Metric.LITRE
 			.withPrefix(Metric.MICRO);
 	public static final LinearUnit MILLILITRE = Metric.LITRE
@@ -427,7 +427,7 @@ public final class Metric {
 			.withPrefix(Metric.KILO);
 	public static final LinearUnit MEGALITRE = Metric.LITRE
 			.withPrefix(Metric.MEGA);
-	
+
 	public static final LinearUnit MICROSECOND = Metric.SECOND
 			.withPrefix(Metric.MICRO);
 	public static final LinearUnit MILLISECOND = Metric.SECOND
@@ -436,14 +436,14 @@ public final class Metric {
 			.withPrefix(Metric.KILO);
 	public static final LinearUnit MEGASECOND = Metric.SECOND
 			.withPrefix(Metric.MEGA);
-	
+
 	public static final LinearUnit MICROGRAM = Metric.GRAM
 			.withPrefix(Metric.MICRO);
 	public static final LinearUnit MILLIGRAM = Metric.GRAM
 			.withPrefix(Metric.MILLI);
 	public static final LinearUnit MEGAGRAM = Metric.GRAM
 			.withPrefix(Metric.MEGA);
-	
+
 	public static final LinearUnit MICRONEWTON = Metric.NEWTON
 			.withPrefix(Metric.MICRO);
 	public static final LinearUnit MILLINEWTON = Metric.NEWTON
@@ -452,7 +452,7 @@ public final class Metric {
 			.withPrefix(Metric.KILO);
 	public static final LinearUnit MEGANEWTON = Metric.NEWTON
 			.withPrefix(Metric.MEGA);
-	
+
 	public static final LinearUnit MICROJOULE = Metric.JOULE
 			.withPrefix(Metric.MICRO);
 	public static final LinearUnit MILLIJOULE = Metric.JOULE
@@ -461,7 +461,7 @@ public final class Metric {
 			.withPrefix(Metric.KILO);
 	public static final LinearUnit MEGAJOULE = Metric.JOULE
 			.withPrefix(Metric.MEGA);
-	
+
 	public static final LinearUnit MICROWATT = Metric.WATT
 			.withPrefix(Metric.MICRO);
 	public static final LinearUnit MILLIWATT = Metric.WATT
@@ -470,7 +470,7 @@ public final class Metric {
 			.withPrefix(Metric.KILO);
 	public static final LinearUnit MEGAWATT = Metric.WATT
 			.withPrefix(Metric.MEGA);
-	
+
 	public static final LinearUnit MICROCOULOMB = Metric.COULOMB
 			.withPrefix(Metric.MICRO);
 	public static final LinearUnit MILLICOULOMB = Metric.COULOMB
@@ -479,12 +479,12 @@ public final class Metric {
 			.withPrefix(Metric.KILO);
 	public static final LinearUnit MEGACOULOMB = Metric.COULOMB
 			.withPrefix(Metric.MEGA);
-	
+
 	public static final LinearUnit MICROAMPERE = Metric.AMPERE
 			.withPrefix(Metric.MICRO);
 	public static final LinearUnit MILLIAMPERE = Metric.AMPERE
 			.withPrefix(Metric.MILLI);
-	
+
 	public static final LinearUnit MICROVOLT = Metric.VOLT
 			.withPrefix(Metric.MICRO);
 	public static final LinearUnit MILLIVOLT = Metric.VOLT
@@ -493,16 +493,16 @@ public final class Metric {
 			.withPrefix(Metric.KILO);
 	public static final LinearUnit MEGAVOLT = Metric.VOLT
 			.withPrefix(Metric.MEGA);
-	
+
 	public static final LinearUnit KILOOHM = Metric.OHM.withPrefix(Metric.KILO);
 	public static final LinearUnit MEGAOHM = Metric.OHM.withPrefix(Metric.MEGA);
-	
+
 	// sets of prefixes
 	public static final Set<UnitPrefix> ALL_PREFIXES = Set.of(DEKA, HECTO, KILO,
 			MEGA, GIGA, TERA, PETA, EXA, ZETTA, YOTTA, DECI, CENTI, MILLI, MICRO,
 			NANO, PICO, FEMTO, ATTO, ZEPTO, YOCTO, KIBI, MEBI, GIBI, TEBI, PEBI,
 			EXBI);
-	
+
 	public static final Set<UnitPrefix> DECIMAL_PREFIXES = Set.of(DEKA, HECTO,
 			KILO, MEGA, GIGA, TERA, PETA, EXA, ZETTA, YOTTA, DECI, CENTI, MILLI,
 			MICRO, NANO, PICO, FEMTO, ATTO, ZEPTO, YOCTO);
@@ -514,7 +514,7 @@ public final class Metric {
 			TEBI, PEBI, EXBI);
 	public static final Set<UnitPrefix> REDUCING_PREFIXES = Set.of(DECI, CENTI,
 			MILLI, MICRO, NANO, PICO, FEMTO, ATTO, ZEPTO, YOCTO);
-	
+
 	// You may NOT get SI instances!
 	private Metric() {
 		throw new AssertionError();
diff --git a/src/main/java/sevenUnits/unit/MultiUnit.java b/src/main/java/sevenUnits/unit/MultiUnit.java
index bc240e3..950c547 100644
--- a/src/main/java/sevenUnits/unit/MultiUnit.java
+++ b/src/main/java/sevenUnits/unit/MultiUnit.java
@@ -39,7 +39,7 @@ public final class MultiUnit extends Unitlike<List<Double>> {
 	public static final MultiUnit of(LinearUnit... units) {
 		return of(Arrays.asList(units));
 	}
-	
+
 	/**
 	 * Creates a {@code MultiUnit} from its units. It will not have a name or
 	 * symbol.
@@ -57,12 +57,12 @@ public final class MultiUnit extends Unitlike<List<Double>> {
 		}
 		return new MultiUnit(new ArrayList<>(units), unitBase, NameSymbol.EMPTY);
 	}
-	
+
 	/**
 	 * The units that make up this value.
 	 */
 	private final List<LinearUnit> units;
-	
+
 	/**
 	 * Creates a {@code MultiUnit}.
 	 *
@@ -73,24 +73,24 @@ public final class MultiUnit extends Unitlike<List<Double>> {
 		super(unitBase, ns);
 		this.units = units;
 	}
-	
+
 	@Override
 	protected List<Double> convertFromBase(double value) {
 		final List<Double> values = new ArrayList<>(this.units.size());
 		double temp = value;
-		
+
 		for (final LinearUnit unit : this.units.subList(0,
 				this.units.size() - 1)) {
 			values.add(Math.floor(temp / unit.getConversionFactor()));
 			temp %= unit.getConversionFactor();
 		}
-		
+
 		values.add(this.units.size() - 1,
 				this.units.get(this.units.size() - 1).convertFromBase(temp));
-		
+
 		return values;
 	}
-	
+
 	/**
 	 * Converts a value expressed in this unitlike form to a value expressed in
 	 * {@code other}.
@@ -99,7 +99,7 @@ public final class MultiUnit extends Unitlike<List<Double>> {
 	 *           {@code other.convertFromBase(this.convertToBase(value))}.
 	 *           Therefore, overriding either of those methods will change the
 	 *           output of this method.
-	 * 				
+	 * 
 	 * @param other unit to convert to
 	 * @param value value to convert
 	 * @return converted value
@@ -115,10 +115,10 @@ public final class MultiUnit extends Unitlike<List<Double>> {
 		for (final double d : values) {
 			valueList.add(d);
 		}
-		
+
 		return this.convertTo(other, valueList);
 	}
-	
+
 	/**
 	 * Converts a value expressed in this unitlike form to a value expressed in
 	 * {@code other}.
@@ -127,7 +127,7 @@ public final class MultiUnit extends Unitlike<List<Double>> {
 	 *           {@code other.convertFromBase(this.convertToBase(value))}.
 	 *           Therefore, overriding either of those methods will change the
 	 *           output of this method.
-	 * 				
+	 * 
 	 * @param other unit to convert to
 	 * @param value value to convert
 	 * @return converted value
@@ -142,16 +142,16 @@ public final class MultiUnit extends Unitlike<List<Double>> {
 		for (final double d : values) {
 			valueList.add(d);
 		}
-		
+
 		return this.convertTo(other, valueList);
 	}
-	
+
 	@Override
 	protected double convertToBase(List<Double> value) {
 		if (value.size() != this.units.size())
 			throw new IllegalArgumentException("Wrong number of values for "
 					+ this.units.size() + "-unit MultiUnit.");
-		
+
 		double baseValue = 0;
 		for (int i = 0; i < this.units.size(); i++) {
 			baseValue += value.get(i) * this.units.get(i).getConversionFactor();
diff --git a/src/main/java/sevenUnits/unit/USCustomary.java b/src/main/java/sevenUnits/unit/USCustomary.java
index 459071f..fce829e 100644
--- a/src/main/java/sevenUnits/unit/USCustomary.java
+++ b/src/main/java/sevenUnits/unit/USCustomary.java
@@ -30,10 +30,14 @@ public final class USCustomary {
 	 * @since 2019-11-08
 	 */
 	public static final class Area {
-		public static final LinearUnit SQUARE_SURVEY_FOOT = Length.SURVEY_FOOT.times(Length.SURVEY_FOOT);
-		public static final LinearUnit SQUARE_CHAIN = Length.SURVEY_CHAIN.times(Length.SURVEY_CHAIN);
-		public static final LinearUnit ACRE = Length.SURVEY_CHAIN.times(Length.SURVEY_FURLONG);
-		public static final LinearUnit SECTION = Length.SURVEY_MILE.times(Length.SURVEY_MILE);
+		public static final LinearUnit SQUARE_SURVEY_FOOT = Length.SURVEY_FOOT
+				.times(Length.SURVEY_FOOT);
+		public static final LinearUnit SQUARE_CHAIN = Length.SURVEY_CHAIN
+				.times(Length.SURVEY_CHAIN);
+		public static final LinearUnit ACRE = Length.SURVEY_CHAIN
+				.times(Length.SURVEY_FURLONG);
+		public static final LinearUnit SECTION = Length.SURVEY_MILE
+				.times(Length.SURVEY_MILE);
 		public static final LinearUnit SURVEY_TOWNSHIP = SECTION.times(36);
 	}
 
@@ -52,8 +56,10 @@ public final class USCustomary {
 		public static final LinearUnit YARD = BritishImperial.Length.YARD;
 		public static final LinearUnit MILE = BritishImperial.Length.MILE;
 
-		public static final LinearUnit SURVEY_FOOT = Metric.METRE.times(1200.0 / 3937.0);
-		public static final LinearUnit SURVEY_LINK = SURVEY_FOOT.times(33.0 / 50.0);
+		public static final LinearUnit SURVEY_FOOT = Metric.METRE
+				.times(1200.0 / 3937.0);
+		public static final LinearUnit SURVEY_LINK = SURVEY_FOOT
+				.times(33.0 / 50.0);
 		public static final LinearUnit SURVEY_ROD = SURVEY_FOOT.times(16.5);
 		public static final LinearUnit SURVEY_CHAIN = SURVEY_ROD.times(4);
 		public static final LinearUnit SURVEY_FURLONG = SURVEY_CHAIN.times(10);
@@ -97,7 +103,8 @@ public final class USCustomary {
 		public static final LinearUnit CUBIC_YARD = Length.YARD.toExponent(3);
 		public static final LinearUnit ACRE_FOOT = Area.ACRE.times(Length.FOOT);
 
-		public static final LinearUnit MINIM = Metric.LITRE.withPrefix(Metric.MICRO).times(61.611519921875);
+		public static final LinearUnit MINIM = Metric.LITRE
+				.withPrefix(Metric.MICRO).times(61.611519921875);
 		public static final LinearUnit FLUID_DRAM = MINIM.times(60);
 		public static final LinearUnit TEASPOON = MINIM.times(80);
 		public static final LinearUnit TABLESPOON = TEASPOON.times(3);
@@ -112,7 +119,8 @@ public final class USCustomary {
 		public static final LinearUnit OIL_BARREL = GALLON.times(42);
 		public static final LinearUnit HOGSHEAD = GALLON.times(63);
 
-		public static final LinearUnit DRY_PINT = Metric.LITRE.times(0.5506104713575);
+		public static final LinearUnit DRY_PINT = Metric.LITRE
+				.times(0.5506104713575);
 		public static final LinearUnit DRY_QUART = DRY_PINT.times(2);
 		public static final LinearUnit DRY_GALLON = DRY_QUART.times(4);
 		public static final LinearUnit PECK = DRY_GALLON.times(2);
@@ -128,8 +136,10 @@ public final class USCustomary {
 	public static final LinearUnit KILOCALORIE = BritishImperial.KILOCALORIE;
 	public static final LinearUnit FOOT_POUND = POUND_FORCE.times(Length.FOOT);
 
-	public static final LinearUnit HORSEPOWER = Length.FOOT.times(POUND_FORCE).dividedBy(Metric.MINUTE).times(33000);
-	public static final LinearUnit POUND_PER_SQUARE_INCH = POUND_FORCE.dividedBy(Length.INCH.toExponent(2));
+	public static final LinearUnit HORSEPOWER = Length.FOOT.times(POUND_FORCE)
+			.dividedBy(Metric.MINUTE).times(33000);
+	public static final LinearUnit POUND_PER_SQUARE_INCH = POUND_FORCE
+			.dividedBy(Length.INCH.toExponent(2));
 
 	public static final Unit FAHRENHEIT = BritishImperial.FAHRENHEIT;
 }
diff --git a/src/main/java/sevenUnits/unit/Unit.java b/src/main/java/sevenUnits/unit/Unit.java
index 14478ba..59e928a 100644
--- a/src/main/java/sevenUnits/unit/Unit.java
+++ b/src/main/java/sevenUnits/unit/Unit.java
@@ -59,7 +59,7 @@ public abstract class Unit implements Nameable {
 			final DoubleUnaryOperator converterTo) {
 		return new FunctionalUnit(base, converterFrom, converterTo);
 	}
-	
+
 	/**
 	 * Returns a unit from its base and the functions it uses to convert to and
 	 * from its base.
@@ -87,28 +87,28 @@ public abstract class Unit implements Nameable {
 			final DoubleUnaryOperator converterTo, final NameSymbol ns) {
 		return new FunctionalUnit(base, converterFrom, converterTo, ns);
 	}
-	
+
 	/**
 	 * The combination of units that this unit is based on.
 	 * 
 	 * @since 2019-10-16
 	 */
 	private final ObjectProduct<BaseUnit> unitBase;
-	
+
 	/**
 	 * This unit's name(s) and symbol
 	 * 
 	 * @since 2020-09-07
 	 */
 	private final NameSymbol nameSymbol;
-	
+
 	/**
 	 * Cache storing the result of getDimension()
 	 *
 	 * @since 2019-10-16
 	 */
 	private transient ObjectProduct<BaseDimension> dimension = null;
-	
+
 	/**
 	 * A constructor that constructs {@code BaseUnit} instances.
 	 * 
@@ -121,7 +121,7 @@ public abstract class Unit implements Nameable {
 			throw new AssertionError();
 		this.nameSymbol = nameSymbol;
 	}
-	
+
 	/**
 	 * Creates the {@code Unit}.
 	 * 
@@ -135,7 +135,7 @@ public abstract class Unit implements Nameable {
 				"unitBase may not be null");
 		this.nameSymbol = Objects.requireNonNull(ns, "ns may not be null");
 	}
-	
+
 	/**
 	 * @return this unit as a {@link Unitlike}
 	 * @since 2020-09-07
@@ -144,7 +144,7 @@ public abstract class Unit implements Nameable {
 		return Unitlike.fromConversionFunctions(this.getBase(),
 				this::convertFromBase, this::convertToBase, this.getNameSymbol());
 	}
-	
+
 	/**
 	 * Checks if a value expressed in this unit can be converted to a value
 	 * expressed in {@code other}
@@ -159,7 +159,7 @@ public abstract class Unit implements Nameable {
 		Objects.requireNonNull(other, "other must not be null.");
 		return Objects.equals(this.getBase(), other.getBase());
 	}
-	
+
 	/**
 	 * Checks if a value expressed in this unit can be converted to a value
 	 * expressed in {@code other}
@@ -174,7 +174,7 @@ public abstract class Unit implements Nameable {
 		Objects.requireNonNull(other, "other must not be null.");
 		return Objects.equals(this.getBase(), other.getBase());
 	}
-	
+
 	/**
 	 * Converts from a value expressed in this unit's base unit to a value
 	 * expressed in this unit.
@@ -190,14 +190,14 @@ public abstract class Unit implements Nameable {
 	 * 
 	 * @implSpec This method is used by {@link #convertTo}, and its behaviour
 	 *           affects the behaviour of {@code convertTo}.
-	 * 				
+	 * 
 	 * @param value value expressed in <b>base</b> unit
 	 * @return value expressed in <b>this</b> unit
 	 * @since 2018-12-22
 	 * @since v0.1.0
 	 */
 	protected abstract double convertFromBase(double value);
-	
+
 	/**
 	 * Converts a value expressed in this unit to a value expressed in
 	 * {@code other}.
@@ -206,7 +206,7 @@ public abstract class Unit implements Nameable {
 	 *           {@code other.convertFromBase(this.convertToBase(value))}.
 	 *           Therefore, overriding either of those methods will change the
 	 *           output of this method.
-	 * 				
+	 * 
 	 * @param other unit to convert to
 	 * @param value value to convert
 	 * @return converted value
@@ -224,7 +224,7 @@ public abstract class Unit implements Nameable {
 			throw new IllegalArgumentException(
 					String.format("Cannot convert from %s to %s.", this, other));
 	}
-	
+
 	/**
 	 * Converts a value expressed in this unit to a value expressed in
 	 * {@code other}.
@@ -252,7 +252,7 @@ public abstract class Unit implements Nameable {
 			throw new IllegalArgumentException(
 					String.format("Cannot convert from %s to %s.", this, other));
 	}
-	
+
 	/**
 	 * Converts from a value expressed in this unit to a value expressed in this
 	 * unit's base unit.
@@ -268,14 +268,14 @@ public abstract class Unit implements Nameable {
 	 * 
 	 * @implSpec This method is used by {@link #convertTo}, and its behaviour
 	 *           affects the behaviour of {@code convertTo}.
-	 * 				
+	 * 
 	 * @param value value expressed in <b>this</b> unit
 	 * @return value expressed in <b>base</b> unit
 	 * @since 2018-12-22
 	 * @since v0.1.0
 	 */
 	protected abstract double convertToBase(double value);
-	
+
 	/**
 	 * @return combination of units that this unit is based on
 	 * @since 2018-12-22
@@ -284,7 +284,7 @@ public abstract class Unit implements Nameable {
 	public final ObjectProduct<BaseUnit> getBase() {
 		return this.unitBase;
 	}
-	
+
 	/**
 	 * @return dimension measured by this unit
 	 * @since 2018-12-22
@@ -294,16 +294,16 @@ public abstract class Unit implements Nameable {
 		if (this.dimension == null) {
 			final Map<BaseUnit, Integer> mapping = this.unitBase.exponentMap();
 			final Map<BaseDimension, Integer> dimensionMap = new HashMap<>();
-			
+
 			for (final BaseUnit key : mapping.keySet()) {
 				dimensionMap.put(key.getBaseDimension(), mapping.get(key));
 			}
-			
+
 			this.dimension = ObjectProduct.fromExponentMapping(dimensionMap);
 		}
 		return this.dimension;
 	}
-	
+
 	/**
 	 * @return the nameSymbol
 	 * @since 2020-09-07
@@ -312,7 +312,7 @@ public abstract class Unit implements Nameable {
 	public final NameSymbol getNameSymbol() {
 		return this.nameSymbol;
 	}
-	
+
 	/**
 	 * Returns true iff this unit is metric.
 	 * <p>
@@ -337,18 +337,18 @@ public abstract class Unit implements Nameable {
 		if (!(this instanceof LinearUnit))
 			return false;
 		final LinearUnit linear = (LinearUnit) this;
-		
+
 		// second condition - check that
 		for (final BaseUnit b : linear.getBase().getBaseSet()) {
 			if (!Metric.BaseUnits.BASE_UNITS.contains(b))
 				return false;
 		}
-		
+
 		// third condition - check that conversion factor is a power of 10
 		return DecimalComparison
 				.equals(Math.log10(linear.getConversionFactor()) % 1.0, 0);
 	}
-	
+
 	/**
 	 * @return a string representing this unit's definition
 	 * @since 2022-03-10
@@ -360,7 +360,7 @@ public abstract class Unit implements Nameable {
 			return "derived from "
 					+ this.getBase().toString(BaseUnit::getShortName);
 	}
-	
+
 	/**
 	 * @return a string containing both this unit's name and its definition
 	 * @since 2022-03-10
@@ -368,7 +368,7 @@ public abstract class Unit implements Nameable {
 	public final String toFullString() {
 		return this.toString() + " (" + this.toDefinitionString() + ")";
 	}
-	
+
 	@Override
 	public String toString() {
 		if (this.nameSymbol.getPrimaryName().isPresent()
@@ -378,7 +378,7 @@ public abstract class Unit implements Nameable {
 		else
 			return this.getName();
 	}
-	
+
 	/**
 	 * @param ns name(s) and symbol to use
 	 * @return a copy of this unit with provided name(s) and symbol
diff --git a/src/main/java/sevenUnits/unit/UnitDatabase.java b/src/main/java/sevenUnits/unit/UnitDatabase.java
index 12b78a7..0120067 100644
--- a/src/main/java/sevenUnits/unit/UnitDatabase.java
+++ b/src/main/java/sevenUnits/unit/UnitDatabase.java
@@ -1,5 +1,5 @@
 /**
- * Copyright (C) 2018 Adrien Hopkins
+ * Copyright (C) 2018-2024 Adrien Hopkins
  *
  * This program is free software: you can redistribute it and/or modify
  * it under the terms of the GNU Affero General Public License as published by
@@ -123,7 +123,7 @@ public final class UnitDatabase {
 					implements Entry<String, Unit> {
 				private final String key;
 				private final Unit value;
-				
+
 				/**
 				 * Creates the {@code PrefixedUnitEntry}.
 				 * 
@@ -136,7 +136,7 @@ public final class UnitDatabase {
 					this.key = key;
 					this.value = value;
 				}
-				
+
 				/**
 				 * @since 2019-05-03
 				 */
@@ -148,17 +148,17 @@ public final class UnitDatabase {
 					return Objects.equals(this.getKey(), other.getKey())
 							&& Objects.equals(this.getValue(), other.getValue());
 				}
-				
+
 				@Override
 				public String getKey() {
 					return this.key;
 				}
-				
+
 				@Override
 				public Unit getValue() {
 					return this.value;
 				}
-				
+
 				/**
 				 * @since 2019-05-03
 				 */
@@ -168,13 +168,13 @@ public final class UnitDatabase {
 							^ (this.getValue() == null ? 0
 									: this.getValue().hashCode());
 				}
-				
+
 				@Override
 				public Unit setValue(final Unit value) {
 					throw new UnsupportedOperationException(
 							"Cannot set value in an immutable entry");
 				}
-				
+
 				/**
 				 * Returns a string representation of the entry. The format of the
 				 * string is the string representation of the key, then the equals
@@ -188,7 +188,7 @@ public final class UnitDatabase {
 					return this.getKey() + "=" + this.getValue();
 				}
 			}
-			
+
 			/**
 			 * An iterator that iterates over the units of a
 			 * {@code PrefixedUnitNameSet}.
@@ -203,12 +203,12 @@ public final class UnitDatabase {
 				private int unitNamePosition = 0;
 				// the indices of the prefixes attached to the current unit
 				private final List<Integer> prefixCoordinates = new ArrayList<>();
-				
+
 				// values from the unit entry set
 				private final Map<String, Unit> map;
 				private transient final List<String> unitNames;
 				private transient final List<String> prefixNames;
-				
+
 				/**
 				 * Creates the
 				 * {@code UnitsDatabase.PrefixedUnitMap.PrefixedUnitNameSet.PrefixedUnitNameIterator}.
@@ -221,7 +221,7 @@ public final class UnitDatabase {
 					this.unitNames = new ArrayList<>(map.units.keySet());
 					this.prefixNames = new ArrayList<>(map.prefixes.keySet());
 				}
-				
+
 				/**
 				 * @return current unit name
 				 * @since 2019-04-14
@@ -233,10 +233,10 @@ public final class UnitDatabase {
 						unitName.append(this.prefixNames.get(i));
 					}
 					unitName.append(this.unitNames.get(this.unitNamePosition));
-					
+
 					return unitName.toString();
 				}
-				
+
 				@Override
 				public boolean hasNext() {
 					if (this.unitNames.isEmpty())
@@ -249,7 +249,7 @@ public final class UnitDatabase {
 							return true;
 					}
 				}
-				
+
 				/**
 				 * Changes this iterator's position to the next available one.
 				 * 
@@ -258,11 +258,11 @@ public final class UnitDatabase {
 				 */
 				private void incrementPosition() {
 					this.unitNamePosition++;
-					
+
 					if (this.unitNamePosition >= this.unitNames.size()) {
 						// we have used all of our units, go to a different prefix
 						this.unitNamePosition = 0;
-						
+
 						// if the prefix coordinates are empty, then set it to [0]
 						if (this.prefixCoordinates.isEmpty()) {
 							this.prefixCoordinates.add(0, 0);
@@ -271,7 +271,7 @@ public final class UnitDatabase {
 							int i = this.prefixCoordinates.size() - 1;
 							this.prefixCoordinates.set(i,
 									this.prefixCoordinates.get(i) + 1);
-							
+
 							// fix any carrying errors
 							while (i >= 0 && this.prefixCoordinates
 									.get(i) >= this.prefixNames.size()) {
@@ -279,7 +279,7 @@ public final class UnitDatabase {
 								this.prefixCoordinates.set(i--, 0); // null and
 																				// decrement at the
 																				// same time
-								
+
 								if (i < 0) { // we need to add a new coordinate
 									this.prefixCoordinates.add(0, 0);
 								} else { // increment an existing one
@@ -290,18 +290,18 @@ public final class UnitDatabase {
 						}
 					}
 				}
-				
+
 				@Override
 				public Entry<String, Unit> next() {
 					// get next element
 					final Entry<String, Unit> nextEntry = this.peek();
-					
+
 					// iterate to next position
 					this.incrementPosition();
-					
+
 					return nextEntry;
 				}
-				
+
 				/**
 				 * @return the next element in the iterator, without iterating over
 				 *         it
@@ -310,7 +310,7 @@ public final class UnitDatabase {
 				private Entry<String, Unit> peek() {
 					if (!this.hasNext())
 						throw new NoSuchElementException("No units left!");
-						
+
 					// if I have prefixes, ensure I'm not using a nonlinear unit
 					// since all of the unprefixed stuff is done, just remove
 					// nonlinear units
@@ -321,12 +321,12 @@ public final class UnitDatabase {
 							this.unitNames.remove(this.unitNamePosition);
 						}
 					}
-					
+
 					final String nextName = this.getCurrentUnitName();
-					
+
 					return new PrefixedUnitEntry(nextName, this.map.get(nextName));
 				}
-				
+
 				/**
 				 * Returns a string representation of the object. The exact details
 				 * of the representation are unspecified and subject to change.
@@ -340,10 +340,10 @@ public final class UnitDatabase {
 							this.peek());
 				}
 			}
-			
+
 			// the map that created this set
 			private final PrefixedUnitMap map;
-			
+
 			/**
 			 * Creates the {@code PrefixedUnitNameSet}.
 			 * 
@@ -354,31 +354,31 @@ public final class UnitDatabase {
 			public PrefixedUnitEntrySet(final PrefixedUnitMap map) {
 				this.map = map;
 			}
-			
+
 			@Override
 			public boolean add(final Map.Entry<String, Unit> e) {
 				throw new UnsupportedOperationException(
 						"Cannot add to an immutable set");
 			}
-			
+
 			@Override
 			public boolean addAll(
 					final Collection<? extends Map.Entry<String, Unit>> c) {
 				throw new UnsupportedOperationException(
 						"Cannot add to an immutable set");
 			}
-			
+
 			@Override
 			public void clear() {
 				throw new UnsupportedOperationException(
 						"Cannot clear an immutable set");
 			}
-			
+
 			@Override
 			public boolean contains(final Object o) {
 				// get the entry
 				final Entry<String, Unit> entry;
-				
+
 				try {
 					// This is OK because I'm in a try-catch block, catching the
 					// exact exception that would be thrown.
@@ -389,11 +389,11 @@ public final class UnitDatabase {
 					throw new IllegalArgumentException(
 							"Attempted to test for an entry using a non-entry.");
 				}
-				
+
 				return this.map.containsKey(entry.getKey())
 						&& this.map.get(entry.getKey()).equals(entry.getValue());
 			}
-			
+
 			@Override
 			public boolean containsAll(final Collection<?> c) {
 				for (final Object o : c)
@@ -401,42 +401,42 @@ public final class UnitDatabase {
 						return false;
 				return true;
 			}
-			
+
 			@Override
 			public boolean isEmpty() {
 				return this.map.isEmpty();
 			}
-			
+
 			@Override
 			public Iterator<Entry<String, Unit>> iterator() {
 				return new PrefixedUnitEntryIterator(this.map);
 			}
-			
+
 			@Override
 			public boolean remove(final Object o) {
 				throw new UnsupportedOperationException(
 						"Cannot remove from an immutable set");
 			}
-			
+
 			@Override
 			public boolean removeAll(final Collection<?> c) {
 				throw new UnsupportedOperationException(
 						"Cannot remove from an immutable set");
 			}
-			
+
 			@Override
 			public boolean removeIf(
 					final Predicate<? super Entry<String, Unit>> filter) {
 				throw new UnsupportedOperationException(
 						"Cannot remove from an immutable set");
 			}
-			
+
 			@Override
 			public boolean retainAll(final Collection<?> c) {
 				throw new UnsupportedOperationException(
 						"Cannot remove from an immutable set");
 			}
-			
+
 			@Override
 			public int size() {
 				if (this.map.units.isEmpty())
@@ -449,7 +449,7 @@ public final class UnitDatabase {
 						return Integer.MAX_VALUE;
 				}
 			}
-			
+
 			/**
 			 * @throws IllegalStateException if the set is infinite in size
 			 */
@@ -462,7 +462,7 @@ public final class UnitDatabase {
 					throw new IllegalStateException(
 							"Cannot make an infinite set into an array.");
 			}
-			
+
 			/**
 			 * @throws IllegalStateException if the set is infinite in size
 			 */
@@ -475,7 +475,7 @@ public final class UnitDatabase {
 					throw new IllegalStateException(
 							"Cannot make an infinite set into an array.");
 			}
-			
+
 			@Override
 			public String toString() {
 				if (this.map.units.isEmpty() || this.map.prefixes.isEmpty())
@@ -486,7 +486,7 @@ public final class UnitDatabase {
 							this.map.units, this.map.prefixes);
 			}
 		}
-		
+
 		/**
 		 * The class used for unit name sets.
 		 * 
@@ -518,12 +518,12 @@ public final class UnitDatabase {
 				private int unitNamePosition = 0;
 				// the indices of the prefixes attached to the current unit
 				private final List<Integer> prefixCoordinates = new ArrayList<>();
-				
+
 				// values from the unit name set
 				private final Map<String, Unit> map;
 				private transient final List<String> unitNames;
 				private transient final List<String> prefixNames;
-				
+
 				/**
 				 * Creates the
 				 * {@code UnitsDatabase.PrefixedUnitMap.PrefixedUnitNameSet.PrefixedUnitNameIterator}.
@@ -536,7 +536,7 @@ public final class UnitDatabase {
 					this.unitNames = new ArrayList<>(map.units.keySet());
 					this.prefixNames = new ArrayList<>(map.prefixes.keySet());
 				}
-				
+
 				/**
 				 * @return current unit name
 				 * @since 2019-04-14
@@ -548,10 +548,10 @@ public final class UnitDatabase {
 						unitName.append(this.prefixNames.get(i));
 					}
 					unitName.append(this.unitNames.get(this.unitNamePosition));
-					
+
 					return unitName.toString();
 				}
-				
+
 				@Override
 				public boolean hasNext() {
 					if (this.unitNames.isEmpty())
@@ -564,7 +564,7 @@ public final class UnitDatabase {
 							return true;
 					}
 				}
-				
+
 				/**
 				 * Changes this iterator's position to the next available one.
 				 * 
@@ -573,11 +573,11 @@ public final class UnitDatabase {
 				 */
 				private void incrementPosition() {
 					this.unitNamePosition++;
-					
+
 					if (this.unitNamePosition >= this.unitNames.size()) {
 						// we have used all of our units, go to a different prefix
 						this.unitNamePosition = 0;
-						
+
 						// if the prefix coordinates are empty, then set it to [0]
 						if (this.prefixCoordinates.isEmpty()) {
 							this.prefixCoordinates.add(0, 0);
@@ -586,7 +586,7 @@ public final class UnitDatabase {
 							int i = this.prefixCoordinates.size() - 1;
 							this.prefixCoordinates.set(i,
 									this.prefixCoordinates.get(i) + 1);
-							
+
 							// fix any carrying errors
 							while (i >= 0 && this.prefixCoordinates
 									.get(i) >= this.prefixNames.size()) {
@@ -594,7 +594,7 @@ public final class UnitDatabase {
 								this.prefixCoordinates.set(i--, 0); // null and
 																				// decrement at the
 																				// same time
-								
+
 								if (i < 0) { // we need to add a new coordinate
 									this.prefixCoordinates.add(0, 0);
 								} else { // increment an existing one
@@ -605,16 +605,16 @@ public final class UnitDatabase {
 						}
 					}
 				}
-				
+
 				@Override
 				public String next() {
 					final String nextName = this.peek();
-					
+
 					this.incrementPosition();
-					
+
 					return nextName;
 				}
-				
+
 				/**
 				 * @return the next element in the iterator, without iterating over
 				 *         it
@@ -633,10 +633,10 @@ public final class UnitDatabase {
 							this.unitNames.remove(this.unitNamePosition);
 						}
 					}
-					
+
 					return this.getCurrentUnitName();
 				}
-				
+
 				/**
 				 * Returns a string representation of the object. The exact details
 				 * of the representation are unspecified and subject to change.
@@ -650,10 +650,10 @@ public final class UnitDatabase {
 							this.peek());
 				}
 			}
-			
+
 			// the map that created this set
 			private final PrefixedUnitMap map;
-			
+
 			/**
 			 * Creates the {@code PrefixedUnitNameSet}.
 			 * 
@@ -664,30 +664,30 @@ public final class UnitDatabase {
 			public PrefixedUnitNameSet(final PrefixedUnitMap map) {
 				this.map = map;
 			}
-			
+
 			@Override
 			public boolean add(final String e) {
 				throw new UnsupportedOperationException(
 						"Cannot add to an immutable set");
 			}
-			
+
 			@Override
 			public boolean addAll(final Collection<? extends String> c) {
 				throw new UnsupportedOperationException(
 						"Cannot add to an immutable set");
 			}
-			
+
 			@Override
 			public void clear() {
 				throw new UnsupportedOperationException(
 						"Cannot clear an immutable set");
 			}
-			
+
 			@Override
 			public boolean contains(final Object o) {
 				return this.map.containsKey(o);
 			}
-			
+
 			@Override
 			public boolean containsAll(final Collection<?> c) {
 				for (final Object o : c)
@@ -695,41 +695,41 @@ public final class UnitDatabase {
 						return false;
 				return true;
 			}
-			
+
 			@Override
 			public boolean isEmpty() {
 				return this.map.isEmpty();
 			}
-			
+
 			@Override
 			public Iterator<String> iterator() {
 				return new PrefixedUnitNameIterator(this.map);
 			}
-			
+
 			@Override
 			public boolean remove(final Object o) {
 				throw new UnsupportedOperationException(
 						"Cannot remove from an immutable set");
 			}
-			
+
 			@Override
 			public boolean removeAll(final Collection<?> c) {
 				throw new UnsupportedOperationException(
 						"Cannot remove from an immutable set");
 			}
-			
+
 			@Override
 			public boolean removeIf(final Predicate<? super String> filter) {
 				throw new UnsupportedOperationException(
 						"Cannot remove from an immutable set");
 			}
-			
+
 			@Override
 			public boolean retainAll(final Collection<?> c) {
 				throw new UnsupportedOperationException(
 						"Cannot remove from an immutable set");
 			}
-			
+
 			@Override
 			public int size() {
 				if (this.map.units.isEmpty())
@@ -742,7 +742,7 @@ public final class UnitDatabase {
 						return Integer.MAX_VALUE;
 				}
 			}
-			
+
 			/**
 			 * @throws IllegalStateException if the set is infinite in size
 			 */
@@ -754,9 +754,9 @@ public final class UnitDatabase {
 					// infinite set
 					throw new IllegalStateException(
 							"Cannot make an infinite set into an array.");
-				
+
 			}
-			
+
 			/**
 			 * @throws IllegalStateException if the set is infinite in size
 			 */
@@ -769,7 +769,7 @@ public final class UnitDatabase {
 					throw new IllegalStateException(
 							"Cannot make an infinite set into an array.");
 			}
-			
+
 			@Override
 			public String toString() {
 				if (this.map.units.isEmpty() || this.map.prefixes.isEmpty())
@@ -780,7 +780,7 @@ public final class UnitDatabase {
 							this.map.units, this.map.prefixes);
 			}
 		}
-		
+
 		/**
 		 * The units stored in this collection, without prefixes.
 		 * 
@@ -788,7 +788,7 @@ public final class UnitDatabase {
 		 * @since v0.2.0
 		 */
 		private final Map<String, Unit> units;
-		
+
 		/**
 		 * The available prefixes for use.
 		 * 
@@ -796,12 +796,12 @@ public final class UnitDatabase {
 		 * @since v0.2.0
 		 */
 		private final Map<String, UnitPrefix> prefixes;
-		
+
 		// caches
 		private transient Collection<Unit> values = null;
 		private transient Set<String> keySet = null;
 		private transient Set<Entry<String, Unit>> entrySet = null;
-		
+
 		/**
 		 * Creates the {@code PrefixedUnitMap}.
 		 * 
@@ -817,50 +817,50 @@ public final class UnitDatabase {
 			this.units = Collections.unmodifiableMap(units);
 			this.prefixes = Collections.unmodifiableMap(prefixes);
 		}
-		
+
 		@Override
 		public void clear() {
 			throw new UnsupportedOperationException(
 					"Cannot clear an immutable map");
 		}
-		
+
 		@Override
 		public Unit compute(final String key,
 				final BiFunction<? super String, ? super Unit, ? extends Unit> remappingFunction) {
 			throw new UnsupportedOperationException(
 					"Cannot edit an immutable map");
 		}
-		
+
 		@Override
 		public Unit computeIfAbsent(final String key,
 				final Function<? super String, ? extends Unit> mappingFunction) {
 			throw new UnsupportedOperationException(
 					"Cannot edit an immutable map");
 		}
-		
+
 		@Override
 		public Unit computeIfPresent(final String key,
 				final BiFunction<? super String, ? super Unit, ? extends Unit> remappingFunction) {
 			throw new UnsupportedOperationException(
 					"Cannot edit an immutable map");
 		}
-		
+
 		@Override
 		public boolean containsKey(final Object key) {
 			// First, test if there is a unit with the key
 			if (this.units.containsKey(key))
 				return true;
-			
+
 			// Next, try to cast it to String
 			if (!(key instanceof String))
 				throw new IllegalArgumentException(
 						"Attempted to test for a unit using a non-string name.");
 			final String unitName = (String) key;
-			
+
 			// Then, look for the longest prefix that is attached to a valid unit
 			String longestPrefix = null;
 			int longestLength = 0;
-			
+
 			for (final String prefixName : this.prefixes.keySet()) {
 				// a prefix name is valid if:
 				// - it is prefixed (i.e. the unit name starts with it)
@@ -879,10 +879,10 @@ public final class UnitDatabase {
 					}
 				}
 			}
-			
+
 			return longestPrefix != null;
 		}
-		
+
 		/**
 		 * {@inheritDoc}
 		 * 
@@ -895,7 +895,7 @@ public final class UnitDatabase {
 		public boolean containsValue(final Object value) {
 			return this.units.containsValue(value);
 		}
-		
+
 		@Override
 		public Set<Entry<String, Unit>> entrySet() {
 			if (this.entrySet == null) {
@@ -903,23 +903,23 @@ public final class UnitDatabase {
 			}
 			return this.entrySet;
 		}
-		
+
 		@Override
 		public Unit get(final Object key) {
 			// First, test if there is a unit with the key
 			if (this.units.containsKey(key))
 				return this.units.get(key);
-			
+
 			// Next, try to cast it to String
 			if (!(key instanceof String))
 				throw new IllegalArgumentException(
 						"Attempted to obtain a unit using a non-string name.");
 			final String unitName = (String) key;
-			
+
 			// Then, look for the longest prefix that is attached to a valid unit
 			String longestPrefix = null;
 			int longestLength = 0;
-			
+
 			for (final String prefixName : this.prefixes.keySet()) {
 				// a prefix name is valid if:
 				// - it is prefixed (i.e. the unit name starts with it)
@@ -938,7 +938,7 @@ public final class UnitDatabase {
 					}
 				}
 			}
-			
+
 			// if none found, returns null
 			if (longestPrefix == null)
 				return null;
@@ -949,16 +949,16 @@ public final class UnitDatabase {
 				// before selecting this prefix
 				final LinearUnit unit = (LinearUnit) this.get(rest);
 				final UnitPrefix prefix = this.prefixes.get(longestPrefix);
-				
+
 				return unit.withPrefix(prefix);
 			}
 		}
-		
+
 		@Override
 		public boolean isEmpty() {
 			return this.units.isEmpty();
 		}
-		
+
 		@Override
 		public Set<String> keySet() {
 			if (this.keySet == null) {
@@ -966,64 +966,64 @@ public final class UnitDatabase {
 			}
 			return this.keySet;
 		}
-		
+
 		@Override
 		public Unit merge(final String key, final Unit value,
 				final BiFunction<? super Unit, ? super Unit, ? extends Unit> remappingFunction) {
 			throw new UnsupportedOperationException(
 					"Cannot merge into an immutable map");
 		}
-		
+
 		@Override
 		public Unit put(final String key, final Unit value) {
 			throw new UnsupportedOperationException(
 					"Cannot add entries to an immutable map");
 		}
-		
+
 		@Override
 		public void putAll(final Map<? extends String, ? extends Unit> m) {
 			throw new UnsupportedOperationException(
 					"Cannot add entries to an immutable map");
 		}
-		
+
 		@Override
 		public Unit putIfAbsent(final String key, final Unit value) {
 			throw new UnsupportedOperationException(
 					"Cannot add entries to an immutable map");
 		}
-		
+
 		@Override
 		public Unit remove(final Object key) {
 			throw new UnsupportedOperationException(
 					"Cannot remove entries from an immutable map");
 		}
-		
+
 		@Override
 		public boolean remove(final Object key, final Object value) {
 			throw new UnsupportedOperationException(
 					"Cannot remove entries from an immutable map");
 		}
-		
+
 		@Override
 		public Unit replace(final String key, final Unit value) {
 			throw new UnsupportedOperationException(
 					"Cannot replace entries in an immutable map");
 		}
-		
+
 		@Override
 		public boolean replace(final String key, final Unit oldValue,
 				final Unit newValue) {
 			throw new UnsupportedOperationException(
 					"Cannot replace entries in an immutable map");
 		}
-		
+
 		@Override
 		public void replaceAll(
 				final BiFunction<? super String, ? super Unit, ? extends Unit> function) {
 			throw new UnsupportedOperationException(
 					"Cannot replace entries in an immutable map");
 		}
-		
+
 		@Override
 		public int size() {
 			if (this.units.isEmpty())
@@ -1036,7 +1036,7 @@ public final class UnitDatabase {
 					return Integer.MAX_VALUE;
 			}
 		}
-		
+
 		@Override
 		public String toString() {
 			if (this.units.isEmpty() || this.prefixes.isEmpty())
@@ -1046,7 +1046,7 @@ public final class UnitDatabase {
 						"Infinite map of name-unit entries created from units %s and prefixes %s",
 						this.units, this.prefixes);
 		}
-		
+
 		/**
 		 * {@inheritDoc}
 		 * 
@@ -1064,20 +1064,20 @@ public final class UnitDatabase {
 			return this.values;
 		}
 	}
-	
+
 	/**
 	 * Replacements done to *all* expression types
 	 */
 	private static final Map<Pattern, String> EXPRESSION_REPLACEMENTS = new HashMap<>();
-	
+
 	// add data to expression replacements
 	static {
 		// add spaces around operators
-		for (final String operator : Arrays.asList("\\*", "/", "\\^")) {
+		for (final String operator : Arrays.asList("\\*", "/", "\\|", "\\^")) {
 			EXPRESSION_REPLACEMENTS.put(Pattern.compile(operator),
 					" " + operator + " ");
 		}
-		
+
 		// replace multiple spaces with a single space
 		EXPRESSION_REPLACEMENTS.put(Pattern.compile(" +"), " ");
 		// place brackets around any expression of the form "number unit", with or
@@ -1092,20 +1092,20 @@ public final class UnitDatabase {
 									// "1e3")
 		), "\\($1 $2\\)");
 	}
-	
+
 	/**
 	 * A regular expression that separates names and expressions in unit files.
 	 */
 	private static final Pattern NAME_EXPRESSION = Pattern
 			.compile("(\\S+)\\s+(\\S.*)");
-	
+
 	/**
 	 * Like normal string comparisons, but shorter strings are always less than
 	 * longer strings.
 	 */
 	private static final Comparator<String> lengthFirstComparator = Comparator
 			.comparingInt(String::length).thenComparing(Comparator.naturalOrder());
-	
+
 	/**
 	 * The exponent operator
 	 * 
@@ -1132,7 +1132,7 @@ public final class UnitDatabase {
 			// not a number
 			throw new IllegalArgumentException("Exponents must be numbers.");
 	}
-	
+
 	/**
 	 * The exponent operator
 	 * 
@@ -1158,7 +1158,7 @@ public final class UnitDatabase {
 			// not a number
 			throw new IllegalArgumentException("Exponents must be numbers.");
 	}
-	
+
 	/**
 	 * @return true if entry represents a removable duplicate entry of map.
 	 * @since 2021-05-22
@@ -1174,7 +1174,7 @@ public final class UnitDatabase {
 		}
 		return false;
 	}
-	
+
 	/**
 	 * The units in this system, excluding prefixes.
 	 * 
@@ -1182,7 +1182,7 @@ public final class UnitDatabase {
 	 * @since v0.1.0
 	 */
 	private final Map<String, Unit> prefixlessUnits;
-	
+
 	/**
 	 * The unit prefixes in this system.
 	 * 
@@ -1190,7 +1190,7 @@ public final class UnitDatabase {
 	 * @since v0.1.0
 	 */
 	private final Map<String, UnitPrefix> prefixes;
-	
+
 	/**
 	 * The dimensions in this system.
 	 * 
@@ -1198,7 +1198,7 @@ public final class UnitDatabase {
 	 * @since v0.2.0
 	 */
 	private final Map<String, ObjectProduct<BaseDimension>> dimensions;
-	
+
 	/**
 	 * A map mapping strings to units (including prefixes)
 	 * 
@@ -1206,7 +1206,7 @@ public final class UnitDatabase {
 	 * @since v0.2.0
 	 */
 	private final Map<String, Unit> units;
-	
+
 	/**
 	 * The rule that specifies when prefix repetition is allowed. It takes in one
 	 * argument: a list of the prefixes being applied to the unit
@@ -1218,7 +1218,7 @@ public final class UnitDatabase {
 	 * {@code prefixRepetitionRule.test(Arrays.asList(giga, mega, kilo))}
 	 */
 	private Predicate<List<UnitPrefix>> prefixRepetitionRule;
-	
+
 	/**
 	 * A parser that can parse unit expressions.
 	 * 
@@ -1227,13 +1227,13 @@ public final class UnitDatabase {
 	 */
 	private final ExpressionParser<LinearUnit> unitExpressionParser = new ExpressionParser.Builder<>(
 			this::getLinearUnit).addBinaryOperator("+", (o1, o2) -> o1.plus(o2), 0)
-					.addBinaryOperator("-", (o1, o2) -> o1.minus(o2), 0)
-					.addBinaryOperator("*", (o1, o2) -> o1.times(o2), 1)
-					.addSpaceFunction("*")
-					.addBinaryOperator("/", (o1, o2) -> o1.dividedBy(o2), 1)
-					.addBinaryOperator("^", UnitDatabase::exponentiateUnits, 2)
-					.build();
-	
+			.addBinaryOperator("-", (o1, o2) -> o1.minus(o2), 0)
+			.addBinaryOperator("*", (o1, o2) -> o1.times(o2), 1)
+			.addSpaceFunction("*")
+			.addBinaryOperator("/", (o1, o2) -> o1.dividedBy(o2), 1)
+			.addBinaryOperator("|", (o1, o2) -> o1.dividedBy(o2), 3)
+			.addBinaryOperator("^", UnitDatabase::exponentiateUnits, 2).build();
+
 	/**
 	 * A parser that can parse unit value expressions.
 	 * 
@@ -1241,14 +1241,15 @@ public final class UnitDatabase {
 	 */
 	private final ExpressionParser<LinearUnitValue> unitValueExpressionParser = new ExpressionParser.Builder<>(
 			this::getLinearUnitValue)
-					.addBinaryOperator("+", (o1, o2) -> o1.plus(o2), 0)
-					.addBinaryOperator("-", (o1, o2) -> o1.minus(o2), 0)
-					.addBinaryOperator("*", (o1, o2) -> o1.times(o2), 1)
-					.addSpaceFunction("*")
-					.addBinaryOperator("/", (o1, o2) -> o1.dividedBy(o2), 1)
-					.addBinaryOperator("^", UnitDatabase::exponentiateUnitValues, 2)
-					.build();
-	
+			.addBinaryOperator("+", (o1, o2) -> o1.plus(o2), 0)
+			.addBinaryOperator("-", (o1, o2) -> o1.minus(o2), 0)
+			.addBinaryOperator("*", (o1, o2) -> o1.times(o2), 1)
+			.addSpaceFunction("*")
+			.addBinaryOperator("/", (o1, o2) -> o1.dividedBy(o2), 1)
+			.addBinaryOperator("|", (o1, o2) -> o1.dividedBy(o2), 3)
+			.addBinaryOperator("^", UnitDatabase::exponentiateUnitValues, 2)
+			.build();
+
 	/**
 	 * A parser that can parse unit prefix expressions
 	 * 
@@ -1256,13 +1257,16 @@ public final class UnitDatabase {
 	 * @since v0.2.0
 	 */
 	private final ExpressionParser<UnitPrefix> prefixExpressionParser = new ExpressionParser.Builder<>(
-			this::getPrefix).addBinaryOperator("*", (o1, o2) -> o1.times(o2), 0)
-					.addSpaceFunction("*")
-					.addBinaryOperator("/", (o1, o2) -> o1.dividedBy(o2), 0)
-					.addBinaryOperator("^",
-							(o1, o2) -> o1.toExponent(o2.getMultiplier()), 1)
-					.build();
-	
+			this::getPrefix).addBinaryOperator("+", (o1, o2) -> o1.plus(o2), 0)
+			.addBinaryOperator("-", (o1, o2) -> o1.minus(o2), 0)
+			.addBinaryOperator("*", (o1, o2) -> o1.times(o2), 1)
+			.addSpaceFunction("*")
+			.addBinaryOperator("/", (o1, o2) -> o1.dividedBy(o2), 1)
+			.addBinaryOperator("|", (o1, o2) -> o1.dividedBy(o2), 3)
+			.addBinaryOperator("^", (o1, o2) -> o1.toExponent(o2.getMultiplier()),
+					2)
+			.build();
+
 	/**
 	 * A parser that can parse unit dimension expressions.
 	 * 
@@ -1271,9 +1275,14 @@ public final class UnitDatabase {
 	 */
 	private final ExpressionParser<ObjectProduct<BaseDimension>> unitDimensionParser = new ExpressionParser.Builder<>(
 			this::getDimension).addBinaryOperator("*", (o1, o2) -> o1.times(o2), 0)
-					.addSpaceFunction("*")
-					.addBinaryOperator("/", (o1, o2) -> o1.dividedBy(o2), 0).build();
-	
+			.addSpaceFunction("*")
+			.addBinaryOperator("/", (o1, o2) -> o1.dividedBy(o2), 0)
+			.addBinaryOperator("|", (o1, o2) -> o1.dividedBy(o2), 2)
+			.addNumericOperator("^", (o1, o2) -> {
+				int exponent = (int) Math.round(o2.value());
+				return o1.toExponent(exponent);
+			}, 1).build();
+
 	/**
 	 * Creates the {@code UnitsDatabase}.
 	 * 
@@ -1283,7 +1292,7 @@ public final class UnitDatabase {
 	public UnitDatabase() {
 		this(prefixes -> true);
 	}
-	
+
 	/**
 	 * Creates the {@code UnitsDatabase}
 	 * 
@@ -1301,7 +1310,7 @@ public final class UnitDatabase {
 				entry -> this.prefixRepetitionRule
 						.test(this.getPrefixesFromName(entry.getKey())));
 	}
-	
+
 	/**
 	 * Adds a unit dimension to the database.
 	 * 
@@ -1319,7 +1328,7 @@ public final class UnitDatabase {
 				.withName(dimension.getNameSymbol().withExtraName(name));
 		this.dimensions.put(name, namedDimension);
 	}
-	
+
 	/**
 	 * Adds to the list from a line in a unit dimension file.
 	 * 
@@ -1338,7 +1347,7 @@ public final class UnitDatabase {
 					lineCounter);
 			return;
 		}
-		
+
 		// divide line into name and expression
 		final Matcher lineMatcher = NAME_EXPRESSION.matcher(line);
 		if (!lineMatcher.matches())
@@ -1347,12 +1356,12 @@ public final class UnitDatabase {
 					lineCounter));
 		final String name = lineMatcher.group(1);
 		final String expression = lineMatcher.group(2);
-		
+
 		// if (name.endsWith(" ")) {
 		// System.err.printf("Warning - line %d's dimension name ends in a space",
 		// lineCounter);
 		// }
-		
+
 		// if expression is "!", search for an existing dimension
 		// if no unit found, throw an error
 		if (expression.equals("!")) {
@@ -1368,11 +1377,11 @@ public final class UnitDatabase {
 				System.err.printf("Parsing error on line %d:%n", lineCounter);
 				throw e;
 			}
-			
+
 			this.addDimension(name, dimension);
 		}
 	}
-	
+
 	/**
 	 * Adds a unit prefix to the database.
 	 * 
@@ -1389,7 +1398,7 @@ public final class UnitDatabase {
 		this.prefixes.put(Objects.requireNonNull(name, "name must not be null."),
 				namedPrefix);
 	}
-	
+
 	/**
 	 * Adds a unit to the database.
 	 * 
@@ -1406,7 +1415,7 @@ public final class UnitDatabase {
 		this.prefixlessUnits.put(
 				Objects.requireNonNull(name, "name must not be null."), namedUnit);
 	}
-	
+
 	/**
 	 * Adds to the list from a line in a unit file.
 	 * 
@@ -1425,7 +1434,7 @@ public final class UnitDatabase {
 					lineCounter);
 			return;
 		}
-		
+
 		// divide line into name and expression
 		final Matcher lineMatcher = NAME_EXPRESSION.matcher(line);
 		if (!lineMatcher.matches())
@@ -1433,15 +1442,15 @@ public final class UnitDatabase {
 					"Error at line %d: Lines of a unit file must consist of a unit name, then spaces or tabs, then a unit expression.",
 					lineCounter));
 		final String name = lineMatcher.group(1);
-		
+
 		final String expression = lineMatcher.group(2);
-		
+
 		// this code should never occur
 		// if (name.endsWith(" ")) {
 		// System.err.printf("Warning - line %d's unit name ends in a space",
 		// lineCounter);
 		// }
-		
+
 		// if expression is "!", search for an existing unit
 		// if no unit found, throw an error
 		if (expression.equals("!")) {
@@ -1474,7 +1483,7 @@ public final class UnitDatabase {
 			}
 		}
 	}
-	
+
 	/**
 	 * Removes all units, prefixes and dimensions from this database.
 	 * 
@@ -1485,7 +1494,7 @@ public final class UnitDatabase {
 		this.prefixes.clear();
 		this.prefixlessUnits.clear();
 	}
-	
+
 	/**
 	 * Tests if the database has a unit dimension with this name.
 	 * 
@@ -1497,7 +1506,7 @@ public final class UnitDatabase {
 	public boolean containsDimensionName(final String name) {
 		return this.dimensions.containsKey(name);
 	}
-	
+
 	/**
 	 * Tests if the database has a unit prefix with this name.
 	 * 
@@ -1509,7 +1518,7 @@ public final class UnitDatabase {
 	public boolean containsPrefixName(final String name) {
 		return this.prefixes.containsKey(name);
 	}
-	
+
 	/**
 	 * Tests if the database has a unit with this name, taking prefixes into
 	 * consideration
@@ -1522,7 +1531,7 @@ public final class UnitDatabase {
 	public boolean containsUnitName(final String name) {
 		return this.units.containsKey(name);
 	}
-	
+
 	/**
 	 * @return a map mapping dimension names to dimensions
 	 * @since 2019-04-13
@@ -1531,7 +1540,7 @@ public final class UnitDatabase {
 	public Map<String, ObjectProduct<BaseDimension>> dimensionMap() {
 		return Collections.unmodifiableMap(this.dimensions);
 	}
-	
+
 	/**
 	 * Evaluates a unit expression, following the same rules as
 	 * {@link #getUnitFromExpression}.
@@ -1542,46 +1551,42 @@ public final class UnitDatabase {
 	 */
 	public LinearUnitValue evaluateUnitExpression(final String expression) {
 		Objects.requireNonNull(expression, "expression must not be null.");
-		
+
 		// attempt to get a unit as an alias, or a number with precision first
 		if (this.containsUnitName(expression))
 			return this.getLinearUnitValue(expression);
-		
+
 		// force operators to have spaces
 		String modifiedExpression = expression;
 		modifiedExpression = modifiedExpression.replaceAll("\\+", " \\+ ");
 		modifiedExpression = modifiedExpression.replaceAll("-", " - ");
-		
+
 		// format expression
 		for (final Entry<Pattern, String> replacement : EXPRESSION_REPLACEMENTS
 				.entrySet()) {
 			modifiedExpression = replacement.getKey().matcher(modifiedExpression)
 					.replaceAll(replacement.getValue());
 		}
-		
+
 		// the previous operation breaks negative numbers, fix them!
 		// (i.e. -2 becomes - 2)
 		// FIXME the previous operaton also breaks stuff like "1e-5"
 		for (int i = 0; i < modifiedExpression.length(); i++) {
 			if (modifiedExpression.charAt(i) == '-'
-					&& (i < 2 || Arrays.asList('+', '-', '*', '/', '^')
+					&& (i < 2 || Arrays.asList('+', '-', '*', '/', '|', '^')
 							.contains(modifiedExpression.charAt(i - 2)))) {
 				// found a broken negative number
 				modifiedExpression = modifiedExpression.substring(0, i + 1)
 						+ modifiedExpression.substring(i + 2);
 			}
 		}
-		
+
 		return this.unitValueExpressionParser.parseExpression(modifiedExpression);
 	}
-	
+
 	/**
 	 * Gets a unit dimension from the database using its name.
 	 * 
-	 * <p>
-	 * This method accepts exponents, like "L^3"
-	 * </p>
-	 * 
 	 * @param name dimension's name
 	 * @return dimension
 	 * @since 2019-03-14
@@ -1589,32 +1594,14 @@ public final class UnitDatabase {
 	 */
 	public ObjectProduct<BaseDimension> getDimension(final String name) {
 		Objects.requireNonNull(name, "name must not be null.");
-		if (name.contains("^")) {
-			final String[] baseAndExponent = name.split("\\^");
-			
-			final ObjectProduct<BaseDimension> base = this
-					.getDimension(baseAndExponent[0]);
-			
-			final int exponent;
-			try {
-				exponent = Integer
-						.parseInt(baseAndExponent[baseAndExponent.length - 1]);
-			} catch (final NumberFormatException e2) {
-				throw new IllegalArgumentException("Exponent must be an integer.");
-			}
-			
-			return base.toExponent(exponent);
-		} else {
-			final ObjectProduct<BaseDimension> dimension = this.dimensions
-					.get(name);
-			if (dimension == null)
-				throw new NoSuchElementException(
-						"No dimension with name \"" + name + "\".");
-			else
-				return dimension;
-		}
+		final ObjectProduct<BaseDimension> dimension = this.dimensions.get(name);
+		if (dimension == null)
+			throw new NoSuchElementException(
+					"No dimension with name \"" + name + "\".");
+		else
+			return dimension;
 	}
-	
+
 	/**
 	 * Uses the database's data to parse an expression into a unit dimension
 	 * <p>
@@ -1637,25 +1624,24 @@ public final class UnitDatabase {
 	public ObjectProduct<BaseDimension> getDimensionFromExpression(
 			final String expression) {
 		Objects.requireNonNull(expression, "expression must not be null.");
-		
+
 		// attempt to get a dimension as an alias first
 		if (this.containsDimensionName(expression))
 			return this.getDimension(expression);
-		
+
 		// force operators to have spaces
 		String modifiedExpression = expression;
-		
+
 		// format expression
 		for (final Entry<Pattern, String> replacement : EXPRESSION_REPLACEMENTS
 				.entrySet()) {
 			modifiedExpression = replacement.getKey().matcher(modifiedExpression)
 					.replaceAll(replacement.getValue());
 		}
-		modifiedExpression = modifiedExpression.replaceAll(" *\\^ *", "\\^");
-		
+
 		return this.unitDimensionParser.parseExpression(modifiedExpression);
 	}
-	
+
 	/**
 	 * Gets a unit. If it is linear, cast it to a LinearUnit and return it.
 	 * Otherwise, throw an {@code IllegalArgumentException}.
@@ -1674,7 +1660,7 @@ public final class UnitDatabase {
 			if (parts.size() != 2)
 				throw new IllegalArgumentException(
 						"Format nonlinear units like: unit(value).");
-			
+
 			// solve the function
 			final Unit unit = this.getUnit(parts.get(0));
 			final double value = Double.parseDouble(
@@ -1683,7 +1669,7 @@ public final class UnitDatabase {
 		} else {
 			// get a linear unit
 			final Unit unit = this.getUnit(name);
-			
+
 			if (unit instanceof LinearUnit)
 				return (LinearUnit) unit;
 			else
@@ -1691,7 +1677,7 @@ public final class UnitDatabase {
 						String.format("%s is not a linear unit.", name));
 		}
 	}
-	
+
 	/**
 	 * Gets a {@code LinearUnitValue} from a unit name. Nonlinear units will be
 	 * converted to their base units.
@@ -1709,7 +1695,7 @@ public final class UnitDatabase {
 			return LinearUnitValue.getExact(this.getLinearUnit(name), 1);
 		}
 	}
-	
+
 	/**
 	 * Gets a unit prefix from the database from its name
 	 * 
@@ -1730,7 +1716,7 @@ public final class UnitDatabase {
 				return prefix;
 		}
 	}
-	
+
 	/**
 	 * Gets all of the prefixes that are on a unit name, in application order.
 	 * 
@@ -1741,12 +1727,12 @@ public final class UnitDatabase {
 	List<UnitPrefix> getPrefixesFromName(final String unitName) {
 		final List<UnitPrefix> prefixes = new ArrayList<>();
 		String name = unitName;
-		
+
 		while (!this.prefixlessUnits.containsKey(name)) {
 			// find the longest prefix
 			String longestPrefixName = null;
 			int longestLength = name.length();
-			
+
 			while (longestPrefixName == null) {
 				longestLength--;
 				if (longestLength <= 0)
@@ -1756,7 +1742,7 @@ public final class UnitDatabase {
 					longestPrefixName = name.substring(0, longestLength);
 				}
 			}
-			
+
 			// longest prefix found!
 			final UnitPrefix prefix = this.getPrefix(longestPrefixName);
 			prefixes.add(0, prefix);
@@ -1764,7 +1750,7 @@ public final class UnitDatabase {
 		}
 		return prefixes;
 	}
-	
+
 	/**
 	 * Gets a unit prefix from a prefix expression
 	 * <p>
@@ -1781,24 +1767,24 @@ public final class UnitDatabase {
 	 */
 	public UnitPrefix getPrefixFromExpression(final String expression) {
 		Objects.requireNonNull(expression, "expression must not be null.");
-		
+
 		// attempt to get a unit as an alias first
 		if (this.containsUnitName(expression))
 			return this.getPrefix(expression);
-		
+
 		// force operators to have spaces
 		String modifiedExpression = expression;
-		
+
 		// format expression
 		for (final Entry<Pattern, String> replacement : EXPRESSION_REPLACEMENTS
 				.entrySet()) {
 			modifiedExpression = replacement.getKey().matcher(modifiedExpression)
 					.replaceAll(replacement.getValue());
 		}
-		
+
 		return this.prefixExpressionParser.parseExpression(modifiedExpression);
 	}
-	
+
 	/**
 	 * @return the prefixRepetitionRule
 	 * @since 2020-08-26
@@ -1806,7 +1792,7 @@ public final class UnitDatabase {
 	public final Predicate<List<UnitPrefix>> getPrefixRepetitionRule() {
 		return this.prefixRepetitionRule;
 	}
-	
+
 	/**
 	 * Gets a unit from the database from its name, looking for prefixes.
 	 * 
@@ -1839,9 +1825,9 @@ public final class UnitDatabase {
 			} else
 				return unit;
 		}
-		
+
 	}
-	
+
 	/**
 	 * Uses the database's unit data to parse an expression into a unit
 	 * <p>
@@ -1865,38 +1851,38 @@ public final class UnitDatabase {
 	 */
 	public Unit getUnitFromExpression(final String expression) {
 		Objects.requireNonNull(expression, "expression must not be null.");
-		
+
 		// attempt to get a unit as an alias first
 		if (this.containsUnitName(expression))
 			return this.getUnit(expression);
-		
+
 		// force operators to have spaces
 		String modifiedExpression = expression;
 		modifiedExpression = modifiedExpression.replaceAll("\\+", " \\+ ");
 		modifiedExpression = modifiedExpression.replaceAll("-", " - ");
-		
+
 		// format expression
 		for (final Entry<Pattern, String> replacement : EXPRESSION_REPLACEMENTS
 				.entrySet()) {
 			modifiedExpression = replacement.getKey().matcher(modifiedExpression)
 					.replaceAll(replacement.getValue());
 		}
-		
+
 		// the previous operation breaks negative numbers, fix them!
 		// (i.e. -2 becomes - 2)
 		for (int i = 0; i < modifiedExpression.length(); i++) {
 			if (modifiedExpression.charAt(i) == '-'
-					&& (i < 2 || Arrays.asList('+', '-', '*', '/', '^')
+					&& (i < 2 || Arrays.asList('+', '-', '*', '/', '|', '^')
 							.contains(modifiedExpression.charAt(i - 2)))) {
 				// found a broken negative number
 				modifiedExpression = modifiedExpression.substring(0, i + 1)
 						+ modifiedExpression.substring(i + 2);
 			}
 		}
-		
+
 		return this.unitExpressionParser.parseExpression(modifiedExpression);
 	}
-	
+
 	/**
 	 * Adds all dimensions from a file, using data from the database to parse
 	 * them.
@@ -1936,7 +1922,7 @@ public final class UnitDatabase {
 			throw new IllegalArgumentException("Could not read file " + file, e);
 		}
 	}
-	
+
 	/**
 	 * Adds all dimensions from a {@code InputStream}. Otherwise, works like
 	 * {@link #loadDimensionFile}.
@@ -1952,7 +1938,7 @@ public final class UnitDatabase {
 			}
 		}
 	}
-	
+
 	/**
 	 * Adds all units from a file, using data from the database to parse them.
 	 * <p>
@@ -1991,7 +1977,7 @@ public final class UnitDatabase {
 			throw new IllegalArgumentException("Could not read file " + file, e);
 		}
 	}
-	
+
 	/**
 	 * Adds all units from a {@code InputStream}. Otherwise, works like
 	 * {@link #loadUnitsFile}.
@@ -2007,7 +1993,7 @@ public final class UnitDatabase {
 			}
 		}
 	}
-	
+
 	/**
 	 * @param includeDuplicates if false, duplicates are removed from the map
 	 * @return a map mapping prefix names to prefixes
@@ -2022,7 +2008,7 @@ public final class UnitDatabase {
 					.conditionalExistenceMap(this.prefixes,
 							entry -> !isRemovableDuplicate(this.prefixes, entry)));
 	}
-	
+
 	/**
 	 * @param prefixRepetitionRule the prefixRepetitionRule to set
 	 * @since 2020-08-26
@@ -2031,7 +2017,7 @@ public final class UnitDatabase {
 			Predicate<List<UnitPrefix>> prefixRepetitionRule) {
 		this.prefixRepetitionRule = prefixRepetitionRule;
 	}
-	
+
 	/**
 	 * @return a string stating the number of units, prefixes and dimensions in
 	 *         the database
@@ -2043,7 +2029,7 @@ public final class UnitDatabase {
 				this.prefixlessUnits.size(), this.prefixes.size(),
 				this.dimensions.size());
 	}
-	
+
 	/**
 	 * Returns a map mapping unit names to units, including units with prefixes.
 	 * <p>
@@ -2075,7 +2061,7 @@ public final class UnitDatabase {
 		return this.units; // PrefixedUnitMap is immutable so I don't need to make
 									// an unmodifiable map.
 	}
-	
+
 	/**
 	 * @param includeDuplicates if true, duplicate units will all exist in the
 	 *                          map; if false, only one of each unit will exist,
diff --git a/src/main/java/sevenUnits/unit/UnitPrefix.java b/src/main/java/sevenUnits/unit/UnitPrefix.java
index e1f7788..9035969 100644
--- a/src/main/java/sevenUnits/unit/UnitPrefix.java
+++ b/src/main/java/sevenUnits/unit/UnitPrefix.java
@@ -40,7 +40,7 @@ public final class UnitPrefix implements Nameable {
 	public static UnitPrefix valueOf(final double multiplier) {
 		return new UnitPrefix(multiplier, NameSymbol.EMPTY);
 	}
-	
+
 	/**
 	 * Gets a {@code UnitPrefix} from a multiplier and a name
 	 * 
@@ -55,21 +55,21 @@ public final class UnitPrefix implements Nameable {
 		return new UnitPrefix(multiplier,
 				Objects.requireNonNull(ns, "ns must not be null."));
 	}
-	
+
 	/**
 	 * This prefix's name(s) and symbol.
 	 * 
 	 * @since 2022-04-16
 	 */
 	private final NameSymbol nameSymbol;
-	
+
 	/**
 	 * The number that this prefix multiplies units by
 	 * 
 	 * @since 2019-10-16
 	 */
 	private final double multiplier;
-	
+
 	/**
 	 * Creates the {@code DefaultUnitPrefix}.
 	 * 
@@ -81,7 +81,7 @@ public final class UnitPrefix implements Nameable {
 		this.multiplier = multiplier;
 		this.nameSymbol = ns;
 	}
-	
+
 	/**
 	 * Divides this prefix by a scalar
 	 * 
@@ -92,7 +92,7 @@ public final class UnitPrefix implements Nameable {
 	public UnitPrefix dividedBy(final double divisor) {
 		return valueOf(this.getMultiplier() / divisor);
 	}
-	
+
 	/**
 	 * Divides this prefix by {@code other}.
 	 * 
@@ -104,7 +104,7 @@ public final class UnitPrefix implements Nameable {
 	public UnitPrefix dividedBy(final UnitPrefix other) {
 		return valueOf(this.getMultiplier() / other.getMultiplier());
 	}
-	
+
 	/**
 	 * {@inheritDoc}
 	 * 
@@ -122,7 +122,7 @@ public final class UnitPrefix implements Nameable {
 		return DecimalComparison.equals(this.getMultiplier(),
 				other.getMultiplier());
 	}
-	
+
 	/**
 	 * @return prefix's multiplier
 	 * @since 2019-11-26
@@ -130,12 +130,12 @@ public final class UnitPrefix implements Nameable {
 	public double getMultiplier() {
 		return this.multiplier;
 	}
-	
+
 	@Override
 	public NameSymbol getNameSymbol() {
 		return this.nameSymbol;
 	}
-	
+
 	/**
 	 * {@inheritDoc}
 	 * 
@@ -145,7 +145,7 @@ public final class UnitPrefix implements Nameable {
 	public int hashCode() {
 		return DecimalComparison.hash(this.getMultiplier());
 	}
-	
+
 	/**
 	 * Multiplies this prefix by a scalar
 	 * 
@@ -156,7 +156,25 @@ public final class UnitPrefix implements Nameable {
 	public UnitPrefix times(final double multiplicand) {
 		return valueOf(this.getMultiplier() * multiplicand);
 	}
-	
+
+	/**
+	 * Adds {@code other} to this prefix and returns the result.
+	 * 
+	 * @since 2024-03-03
+	 */
+	public UnitPrefix plus(final UnitPrefix other) {
+		return valueOf(this.getMultiplier() + other.getMultiplier());
+	}
+
+	/**
+	 * Subtracts {@code other} from this prefix and returns the result.
+	 * 
+	 * @since 2024-03-03
+	 */
+	public UnitPrefix minus(final UnitPrefix other) {
+		return valueOf(this.getMultiplier() - other.getMultiplier());
+	}
+
 	/**
 	 * Multiplies this prefix by {@code other}.
 	 * 
@@ -168,7 +186,7 @@ public final class UnitPrefix implements Nameable {
 	public UnitPrefix times(final UnitPrefix other) {
 		return valueOf(this.getMultiplier() * other.getMultiplier());
 	}
-	
+
 	/**
 	 * Raises this prefix to an exponent.
 	 * 
@@ -180,7 +198,7 @@ public final class UnitPrefix implements Nameable {
 	public UnitPrefix toExponent(final double exponent) {
 		return valueOf(Math.pow(this.getMultiplier(), exponent));
 	}
-	
+
 	/**
 	 * @return a string describing the prefix and its multiplier
 	 */
@@ -195,7 +213,7 @@ public final class UnitPrefix implements Nameable {
 		else
 			return String.format("Unit Prefix (\u00D7 %s)", this.multiplier);
 	}
-	
+
 	/**
 	 * @param ns name(s) and symbol to use
 	 * @return copy of this prefix with provided name(s) and symbol
diff --git a/src/main/java/sevenUnits/unit/UnitType.java b/src/main/java/sevenUnits/unit/UnitType.java
index 7cebf2d..9a87288 100644
--- a/src/main/java/sevenUnits/unit/UnitType.java
+++ b/src/main/java/sevenUnits/unit/UnitType.java
@@ -33,7 +33,7 @@ import java.util.function.Predicate;
  */
 public enum UnitType {
 	METRIC, SEMI_METRIC, NON_METRIC;
-	
+
 	/**
 	 * Determines which type a unit is. The type will be:
 	 * <ul>
diff --git a/src/main/java/sevenUnits/unit/UnitValue.java b/src/main/java/sevenUnits/unit/UnitValue.java
index 339263d..2d01831 100644
--- a/src/main/java/sevenUnits/unit/UnitValue.java
+++ b/src/main/java/sevenUnits/unit/UnitValue.java
@@ -42,10 +42,10 @@ public final class UnitValue {
 		return new UnitValue(
 				Objects.requireNonNull(unit, "unit must not be null"), value);
 	}
-	
+
 	private final Unit unit;
 	private final double value;
-	
+
 	/**
 	 * @param unit  the unit being used
 	 * @param value the value being represented
@@ -54,7 +54,7 @@ public final class UnitValue {
 		this.unit = unit;
 		this.value = value;
 	}
-	
+
 	/**
 	 * @return true if this value can be converted to {@code other}.
 	 * @since 2020-10-01
@@ -62,7 +62,7 @@ public final class UnitValue {
 	public final boolean canConvertTo(Unit other) {
 		return this.unit.canConvertTo(other);
 	}
-	
+
 	/**
 	 * @return true if this value can be converted to {@code other}.
 	 * @since 2020-10-01
@@ -70,7 +70,7 @@ public final class UnitValue {
 	public final <W> boolean canConvertTo(Unitlike<W> other) {
 		return this.unit.canConvertTo(other);
 	}
-	
+
 	/**
 	 * Returns a UnitlikeValue that represents the same value expressed in a
 	 * different unitlike form.
@@ -83,7 +83,7 @@ public final class UnitValue {
 		return UnitlikeValue.of(other,
 				this.unit.convertTo(other, this.getValue()));
 	}
-	
+
 	/**
 	 * Returns a UnitValue that represents the same value expressed in a
 	 * different unit
@@ -95,7 +95,7 @@ public final class UnitValue {
 		return UnitValue.of(other,
 				this.getUnit().convertTo(other, this.getValue()));
 	}
-	
+
 	/**
 	 * Returns this unit value represented as a {@code LinearUnitValue} with this
 	 * unit's base unit as the base.
@@ -108,7 +108,7 @@ public final class UnitValue {
 		final LinearUnit base = LinearUnit.getBase(this.unit).withName(ns);
 		return this.convertToLinear(base);
 	}
-	
+
 	/**
 	 * @return a {@code LinearUnitValue} that is equivalent to this value. It
 	 *         will have zero uncertainty.
@@ -118,7 +118,7 @@ public final class UnitValue {
 		return LinearUnitValue.getExact(other,
 				this.getUnit().convertTo(other, this.getValue()));
 	}
-	
+
 	/**
 	 * Returns true if this and obj represent the same value, regardless of
 	 * whether or not they are expressed in the same unit. So (1000 m).equals(1
@@ -135,7 +135,7 @@ public final class UnitValue {
 								.doubleToLongBits(
 										other.getUnit().convertToBase(other.getValue()));
 	}
-	
+
 	/**
 	 * @return the unit
 	 * @since 2020-09-29
@@ -143,7 +143,7 @@ public final class UnitValue {
 	public final Unit getUnit() {
 		return this.unit;
 	}
-	
+
 	/**
 	 * @return the value
 	 * @since 2020-09-29
@@ -151,13 +151,13 @@ public final class UnitValue {
 	public final double getValue() {
 		return this.value;
 	}
-	
+
 	@Override
 	public int hashCode() {
 		return Objects.hash(this.getUnit().getBase(),
 				this.getUnit().convertFromBase(this.getValue()));
 	}
-	
+
 	@Override
 	public String toString() {
 		final Optional<String> primaryName = this.getUnit().getPrimaryName();
diff --git a/src/main/java/sevenUnits/unit/Unitlike.java b/src/main/java/sevenUnits/unit/Unitlike.java
index 68de2c2..fef424e 100644
--- a/src/main/java/sevenUnits/unit/Unitlike.java
+++ b/src/main/java/sevenUnits/unit/Unitlike.java
@@ -55,7 +55,7 @@ public abstract class Unitlike<V> implements Nameable {
 		return new FunctionalUnitlike<>(base, NameSymbol.EMPTY, converterFrom,
 				converterTo);
 	}
-	
+
 	/**
 	 * Returns a unitlike form from its base and the functions it uses to convert
 	 * to and from its base.
@@ -78,28 +78,28 @@ public abstract class Unitlike<V> implements Nameable {
 			final ToDoubleFunction<W> converterTo, final NameSymbol ns) {
 		return new FunctionalUnitlike<>(base, ns, converterFrom, converterTo);
 	}
-	
+
 	/**
 	 * The combination of units that this unit is based on.
 	 * 
 	 * @since 2019-10-16
 	 */
 	private final ObjectProduct<BaseUnit> unitBase;
-	
+
 	/**
 	 * This unit's name(s) and symbol
 	 * 
 	 * @since 2020-09-07
 	 */
 	private final NameSymbol nameSymbol;
-	
+
 	/**
 	 * Cache storing the result of getDimension()
 	 *
 	 * @since 2019-10-16
 	 */
 	private transient ObjectProduct<BaseDimension> dimension = null;
-	
+
 	/**
 	 * @param unitBase
 	 * @since 2020-09-07
@@ -109,7 +109,7 @@ public abstract class Unitlike<V> implements Nameable {
 				"unitBase may not be null");
 		this.nameSymbol = Objects.requireNonNull(ns, "ns may not be null");
 	}
-	
+
 	/**
 	 * Checks if a value expressed in this unitlike form can be converted to a
 	 * value expressed in {@code other}
@@ -124,7 +124,7 @@ public abstract class Unitlike<V> implements Nameable {
 		Objects.requireNonNull(other, "other must not be null.");
 		return Objects.equals(this.getBase(), other.getBase());
 	}
-	
+
 	/**
 	 * Checks if a value expressed in this unitlike form can be converted to a
 	 * value expressed in {@code other}
@@ -139,9 +139,9 @@ public abstract class Unitlike<V> implements Nameable {
 		Objects.requireNonNull(other, "other must not be null.");
 		return Objects.equals(this.getBase(), other.getBase());
 	}
-	
+
 	protected abstract V convertFromBase(double value);
-	
+
 	/**
 	 * Converts a value expressed in this unitlike form to a value expressed in
 	 * {@code other}.
@@ -150,7 +150,7 @@ public abstract class Unitlike<V> implements Nameable {
 	 *           {@code other.convertFromBase(this.convertToBase(value))}.
 	 *           Therefore, overriding either of those methods will change the
 	 *           output of this method.
-	 * 				
+	 * 
 	 * @param other unit to convert to
 	 * @param value value to convert
 	 * @return converted value
@@ -168,7 +168,7 @@ public abstract class Unitlike<V> implements Nameable {
 			throw new IllegalArgumentException(
 					String.format("Cannot convert from %s to %s.", this, other));
 	}
-	
+
 	/**
 	 * Converts a value expressed in this unitlike form to a value expressed in
 	 * {@code other}.
@@ -196,9 +196,9 @@ public abstract class Unitlike<V> implements Nameable {
 			throw new IllegalArgumentException(
 					String.format("Cannot convert from %s to %s.", this, other));
 	}
-	
+
 	protected abstract double convertToBase(V value);
-	
+
 	/**
 	 * @return combination of units that this unit is based on
 	 * @since 2018-12-22
@@ -207,7 +207,7 @@ public abstract class Unitlike<V> implements Nameable {
 	public final ObjectProduct<BaseUnit> getBase() {
 		return this.unitBase;
 	}
-	
+
 	/**
 	 * @return dimension measured by this unit
 	 * @since 2018-12-22
@@ -217,16 +217,16 @@ public abstract class Unitlike<V> implements Nameable {
 		if (this.dimension == null) {
 			final Map<BaseUnit, Integer> mapping = this.unitBase.exponentMap();
 			final Map<BaseDimension, Integer> dimensionMap = new HashMap<>();
-			
+
 			for (final BaseUnit key : mapping.keySet()) {
 				dimensionMap.put(key.getBaseDimension(), mapping.get(key));
 			}
-			
+
 			this.dimension = ObjectProduct.fromExponentMapping(dimensionMap);
 		}
 		return this.dimension;
 	}
-	
+
 	/**
 	 * @return the nameSymbol
 	 * @since 2020-09-07
@@ -235,7 +235,7 @@ public abstract class Unitlike<V> implements Nameable {
 	public final NameSymbol getNameSymbol() {
 		return this.nameSymbol;
 	}
-	
+
 	@Override
 	public String toString() {
 		return this.getPrimaryName().orElse("Unnamed unitlike form")
@@ -247,7 +247,7 @@ public abstract class Unitlike<V> implements Nameable {
 				+ (this.getOtherNames().isEmpty() ? ""
 						: ", also called " + String.join(", ", this.getOtherNames()));
 	}
-	
+
 	/**
 	 * @param ns name(s) and symbol to use
 	 * @return a copy of this unitlike form with provided name(s) and symbol
diff --git a/src/main/java/sevenUnits/unit/UnitlikeValue.java b/src/main/java/sevenUnits/unit/UnitlikeValue.java
index 26354b1..ad0d1ea 100644
--- a/src/main/java/sevenUnits/unit/UnitlikeValue.java
+++ b/src/main/java/sevenUnits/unit/UnitlikeValue.java
@@ -34,10 +34,10 @@ final class UnitlikeValue<T extends Unitlike<V>, V> {
 			V value) {
 		return new UnitlikeValue<>(unitlike, value);
 	}
-	
+
 	private final T unitlike;
 	private final V value;
-	
+
 	/**
 	 * @param unitlike
 	 * @param value
@@ -47,7 +47,7 @@ final class UnitlikeValue<T extends Unitlike<V>, V> {
 		this.unitlike = unitlike;
 		this.value = value;
 	}
-	
+
 	/**
 	 * @return true if this value can be converted to {@code other}.
 	 * @since 2020-10-01
@@ -55,7 +55,7 @@ final class UnitlikeValue<T extends Unitlike<V>, V> {
 	public final boolean canConvertTo(Unit other) {
 		return this.unitlike.canConvertTo(other);
 	}
-	
+
 	/**
 	 * @return true if this value can be converted to {@code other}.
 	 * @since 2020-10-01
@@ -63,7 +63,7 @@ final class UnitlikeValue<T extends Unitlike<V>, V> {
 	public final <W> boolean canConvertTo(Unitlike<W> other) {
 		return this.unitlike.canConvertTo(other);
 	}
-	
+
 	/**
 	 * Returns a UnitlikeValue that represents the same value expressed in a
 	 * different unitlike form.
@@ -76,7 +76,7 @@ final class UnitlikeValue<T extends Unitlike<V>, V> {
 		return UnitlikeValue.of(other,
 				this.unitlike.convertTo(other, this.getValue()));
 	}
-	
+
 	/**
 	 * Returns a UnitValue that represents the same value expressed in a
 	 * different unit
@@ -88,7 +88,7 @@ final class UnitlikeValue<T extends Unitlike<V>, V> {
 		return UnitValue.of(other,
 				this.unitlike.convertTo(other, this.getValue()));
 	}
-	
+
 	/**
 	 * Returns this unit value represented as a {@code LinearUnitValue} with this
 	 * unit's base unit as the base.
@@ -101,7 +101,7 @@ final class UnitlikeValue<T extends Unitlike<V>, V> {
 		final LinearUnit base = LinearUnit.getBase(this.unitlike).withName(ns);
 		return this.convertToLinear(base);
 	}
-	
+
 	/**
 	 * @return a {@code LinearUnitValue} that is equivalent to this value. It
 	 *         will have zero uncertainty.
@@ -111,7 +111,7 @@ final class UnitlikeValue<T extends Unitlike<V>, V> {
 		return LinearUnitValue.getExact(other,
 				this.getUnitlike().convertTo(other, this.getValue()));
 	}
-	
+
 	@Override
 	public boolean equals(Object obj) {
 		if (this == obj)
@@ -131,7 +131,7 @@ final class UnitlikeValue<T extends Unitlike<V>, V> {
 			return false;
 		return true;
 	}
-	
+
 	/**
 	 * @return the unitlike
 	 * @since 2020-09-29
@@ -139,7 +139,7 @@ final class UnitlikeValue<T extends Unitlike<V>, V> {
 	public final Unitlike<V> getUnitlike() {
 		return this.unitlike;
 	}
-	
+
 	/**
 	 * @return the value
 	 * @since 2020-09-29
@@ -147,7 +147,7 @@ final class UnitlikeValue<T extends Unitlike<V>, V> {
 	public final V getValue() {
 		return this.value;
 	}
-	
+
 	@Override
 	public int hashCode() {
 		final int prime = 31;
@@ -158,7 +158,7 @@ final class UnitlikeValue<T extends Unitlike<V>, V> {
 				+ (this.getValue() == null ? 0 : this.getValue().hashCode());
 		return result;
 	}
-	
+
 	@Override
 	public String toString() {
 		final Optional<String> primaryName = this.getUnitlike().getPrimaryName();
diff --git a/src/main/java/sevenUnits/utils/ConditionalExistenceCollections.java b/src/main/java/sevenUnits/utils/ConditionalExistenceCollections.java
index bee4dd1..b71a4e0 100644
--- a/src/main/java/sevenUnits/utils/ConditionalExistenceCollections.java
+++ b/src/main/java/sevenUnits/utils/ConditionalExistenceCollections.java
@@ -67,7 +67,7 @@ public final class ConditionalExistenceCollections {
 			extends AbstractCollection<E> {
 		final Collection<E> collection;
 		final Predicate<E> existenceCondition;
-		
+
 		/**
 		 * Creates the {@code ConditionalExistenceCollection}.
 		 * 
@@ -80,38 +80,38 @@ public final class ConditionalExistenceCollections {
 			this.collection = collection;
 			this.existenceCondition = existenceCondition;
 		}
-		
+
 		@Override
 		public boolean add(final E e) {
 			return this.collection.add(e) && this.existenceCondition.test(e);
 		}
-		
+
 		@Override
 		public void clear() {
 			this.collection.clear();
 		}
-		
+
 		@Override
 		public boolean contains(final Object o) {
 			if (!this.collection.contains(o))
 				return false;
-				
+
 			// this collection can only contain instances of E
 			// since the object is in the collection, we know that it must be an
 			// instance of E
 			// therefore this cast will always work
 			@SuppressWarnings("unchecked")
 			final E e = (E) o;
-			
+
 			return this.existenceCondition.test(e);
 		}
-		
+
 		@Override
 		public Iterator<E> iterator() {
 			return conditionalExistenceIterator(this.collection.iterator(),
 					this.existenceCondition);
 		}
-		
+
 		@Override
 		public boolean remove(final Object o) {
 			// remove() must be first in the && statement, otherwise it may not
@@ -119,32 +119,32 @@ public final class ConditionalExistenceCollections {
 			final boolean containedObject = this.contains(o);
 			return this.collection.remove(o) && containedObject;
 		}
-		
+
 		@Override
 		public int size() {
 			return (int) this.collection.stream().filter(this.existenceCondition)
 					.count();
 		}
-		
+
 		@Override
 		public Object[] toArray() {
 			// ensure the toArray operation is supported
 			this.collection.toArray();
-			
+
 			// if it works, do it for real
 			return super.toArray();
 		}
-		
+
 		@Override
 		public <T> T[] toArray(T[] a) {
 			// ensure the toArray operation is supported
 			this.collection.toArray();
-			
+
 			// if it works, do it for real
 			return super.toArray(a);
 		}
 	}
-	
+
 	/**
 	 * Elements in this wrapper iterator only exist if they pass a condition.
 	 * 
@@ -157,7 +157,7 @@ public final class ConditionalExistenceCollections {
 		final Predicate<E> existenceCondition;
 		E nextElement;
 		boolean hasNext;
-		
+
 		/**
 		 * Creates the {@code ConditionalExistenceIterator}.
 		 * 
@@ -171,7 +171,7 @@ public final class ConditionalExistenceCollections {
 			this.existenceCondition = condition;
 			this.getAndSetNextElement();
 		}
-		
+
 		/**
 		 * Gets the next element, and sets nextElement and hasNext accordingly.
 		 * 
@@ -188,12 +188,12 @@ public final class ConditionalExistenceCollections {
 			} while (!this.existenceCondition.test(this.nextElement));
 			this.hasNext = true;
 		}
-		
+
 		@Override
 		public boolean hasNext() {
 			return this.hasNext;
 		}
-		
+
 		@Override
 		public E next() {
 			if (this.hasNext()) {
@@ -203,13 +203,13 @@ public final class ConditionalExistenceCollections {
 			} else
 				throw new NoSuchElementException();
 		}
-		
+
 		@Override
 		public void remove() {
 			this.iterator.remove();
 		}
 	}
-	
+
 	/**
 	 * Mappings in this map only exist if the entry passes some condition.
 	 * 
@@ -221,7 +221,7 @@ public final class ConditionalExistenceCollections {
 	static final class ConditionalExistenceMap<K, V> extends AbstractMap<K, V> {
 		Map<K, V> map;
 		Predicate<Entry<K, V>> entryExistenceCondition;
-		
+
 		/**
 		 * Creates the {@code ConditionalExistenceMap}.
 		 * 
@@ -234,81 +234,81 @@ public final class ConditionalExistenceCollections {
 			this.map = map;
 			this.entryExistenceCondition = entryExistenceCondition;
 		}
-		
+
 		@Override
 		public boolean containsKey(final Object key) {
 			if (!this.map.containsKey(key))
 				return false;
-				
+
 			// only instances of K have mappings in the backing map
 			// since we know that key is a valid key, it must be an instance of K
 			@SuppressWarnings("unchecked")
 			final K keyAsK = (K) key;
-			
+
 			// get and test entry
 			final V value = this.map.get(key);
 			final Entry<K, V> entry = new SimpleEntry<>(keyAsK, value);
 			return this.entryExistenceCondition.test(entry);
 		}
-		
+
 		@Override
 		public Set<Entry<K, V>> entrySet() {
 			return conditionalExistenceSet(this.map.entrySet(),
 					this.entryExistenceCondition);
 		}
-		
+
 		@Override
 		public V get(final Object key) {
 			return this.containsKey(key) ? this.map.get(key) : null;
 		}
-		
+
 		private final Entry<K, V> getEntry(K key) {
 			return new Entry<>() {
 				@Override
 				public K getKey() {
 					return key;
 				}
-				
+
 				@Override
 				public V getValue() {
 					return ConditionalExistenceMap.this.map.get(key);
 				}
-				
+
 				@Override
 				public V setValue(V value) {
 					return ConditionalExistenceMap.this.map.put(key, value);
 				}
 			};
 		}
-		
+
 		@Override
 		public Set<K> keySet() {
 			return conditionalExistenceSet(this.map.keySet(),
 					k -> this.entryExistenceCondition.test(this.getEntry(k)));
 		}
-		
+
 		@Override
 		public V put(final K key, final V value) {
 			final V oldValue = this.map.put(key, value);
-			
+
 			// get and test entry
 			final Entry<K, V> entry = new SimpleEntry<>(key, oldValue);
 			return this.entryExistenceCondition.test(entry) ? oldValue : null;
 		}
-		
+
 		@Override
 		public V remove(final Object key) {
 			final V oldValue = this.map.remove(key);
 			return this.containsKey(key) ? oldValue : null;
 		}
-		
+
 		@Override
 		public Collection<V> values() {
 			// maybe change this to use ConditionalExistenceCollection
 			return super.values();
 		}
 	}
-	
+
 	/**
 	 * Elements in this set only exist if a certain condition is true.
 	 * 
@@ -319,7 +319,7 @@ public final class ConditionalExistenceCollections {
 	static final class ConditionalExistenceSet<E> extends AbstractSet<E> {
 		private final Set<E> set;
 		private final Predicate<E> existenceCondition;
-		
+
 		/**
 		 * Creates the {@code ConditionalNonexistenceSet}.
 		 * 
@@ -332,7 +332,7 @@ public final class ConditionalExistenceCollections {
 			this.set = set;
 			this.existenceCondition = existenceCondition;
 		}
-		
+
 		/**
 		 * {@inheritDoc}
 		 * <p>
@@ -343,33 +343,33 @@ public final class ConditionalExistenceCollections {
 		public boolean add(final E e) {
 			return this.set.add(e) && this.existenceCondition.test(e);
 		}
-		
+
 		@Override
 		public void clear() {
 			this.set.clear();
 		}
-		
+
 		@Override
 		public boolean contains(final Object o) {
 			if (!this.set.contains(o))
 				return false;
-				
+
 			// this set can only contain instances of E
 			// since the object is in the set, we know that it must be an instance
 			// of E
 			// therefore this cast will always work
 			@SuppressWarnings("unchecked")
 			final E e = (E) o;
-			
+
 			return this.existenceCondition.test(e);
 		}
-		
+
 		@Override
 		public Iterator<E> iterator() {
 			return conditionalExistenceIterator(this.set.iterator(),
 					this.existenceCondition);
 		}
-		
+
 		@Override
 		public boolean remove(final Object o) {
 			// remove() must be first in the && statement, otherwise it may not
@@ -377,31 +377,31 @@ public final class ConditionalExistenceCollections {
 			final boolean containedObject = this.contains(o);
 			return this.set.remove(o) && containedObject;
 		}
-		
+
 		@Override
 		public int size() {
 			return (int) this.set.stream().filter(this.existenceCondition).count();
 		}
-		
+
 		@Override
 		public Object[] toArray() {
 			// ensure the toArray operation is supported
 			this.set.toArray();
-			
+
 			// if it works, do it for real
 			return super.toArray();
 		}
-		
+
 		@Override
 		public <T> T[] toArray(T[] a) {
 			// ensure the toArray operation is supported
 			this.set.toArray();
-			
+
 			// if it works, do it for real
 			return super.toArray(a);
 		}
 	}
-	
+
 	/**
 	 * Elements in the returned wrapper collection are ignored if they don't pass
 	 * a condition.
@@ -418,7 +418,7 @@ public final class ConditionalExistenceCollections {
 		return new ConditionalExistenceCollection<>(collection,
 				existenceCondition);
 	}
-	
+
 	/**
 	 * Elements in the returned wrapper iterator are ignored if they don't pass a
 	 * condition.
@@ -433,7 +433,7 @@ public final class ConditionalExistenceCollections {
 			final Iterator<E> iterator, final Predicate<E> existenceCondition) {
 		return new ConditionalExistenceIterator<>(iterator, existenceCondition);
 	}
-	
+
 	/**
 	 * Mappings in the returned wrapper map are ignored if the corresponding
 	 * entry doesn't pass a condition
@@ -450,7 +450,7 @@ public final class ConditionalExistenceCollections {
 			final Predicate<Entry<K, V>> entryExistenceCondition) {
 		return new ConditionalExistenceMap<>(map, entryExistenceCondition);
 	}
-	
+
 	/**
 	 * Elements in the returned wrapper set are ignored if they don't pass a
 	 * condition.
diff --git a/src/main/java/sevenUnits/utils/DecimalComparison.java b/src/main/java/sevenUnits/utils/DecimalComparison.java
index a5cbbaa..0515b6b 100644
--- a/src/main/java/sevenUnits/utils/DecimalComparison.java
+++ b/src/main/java/sevenUnits/utils/DecimalComparison.java
@@ -34,7 +34,7 @@ public final class DecimalComparison {
 	 * @since v0.2.0
 	 */
 	public static final double DOUBLE_EPSILON = 1.0e-15;
-	
+
 	/**
 	 * The value used for float comparison. If two float values are within this
 	 * value multiplied by the larger value, they are considered equal.
@@ -43,7 +43,7 @@ public final class DecimalComparison {
 	 * @since v0.2.0
 	 */
 	public static final float FLOAT_EPSILON = 1.0e-6f;
-	
+
 	/**
 	 * Tests for equality of double values using {@link #DOUBLE_EPSILON}.
 	 * <p>
@@ -74,7 +74,7 @@ public final class DecimalComparison {
 	public static final boolean equals(final double a, final double b) {
 		return DecimalComparison.equals(a, b, DOUBLE_EPSILON);
 	}
-	
+
 	/**
 	 * Tests for double equality using a custom epsilon value.
 	 * 
@@ -106,7 +106,7 @@ public final class DecimalComparison {
 			final double epsilon) {
 		return Math.abs(a - b) <= epsilon * Math.max(Math.abs(a), Math.abs(b));
 	}
-	
+
 	/**
 	 * Tests for equality of float values using {@link #FLOAT_EPSILON}.
 	 * 
@@ -136,7 +136,7 @@ public final class DecimalComparison {
 	public static final boolean equals(final float a, final float b) {
 		return DecimalComparison.equals(a, b, FLOAT_EPSILON);
 	}
-	
+
 	/**
 	 * Tests for float equality using a custom epsilon value.
 	 * 
@@ -168,7 +168,7 @@ public final class DecimalComparison {
 			final float epsilon) {
 		return Math.abs(a - b) <= epsilon * Math.max(Math.abs(a), Math.abs(b));
 	}
-	
+
 	/**
 	 * Tests for equality of {@code UncertainDouble} values using
 	 * {@link #DOUBLE_EPSILON}.
@@ -201,7 +201,7 @@ public final class DecimalComparison {
 		return DecimalComparison.equals(a.value(), b.value())
 				&& DecimalComparison.equals(a.uncertainty(), b.uncertainty());
 	}
-	
+
 	/**
 	 * Tests for {@code UncertainDouble} equality using a custom epsilon value.
 	 * 
@@ -235,7 +235,7 @@ public final class DecimalComparison {
 				&& DecimalComparison.equals(a.uncertainty(), b.uncertainty(),
 						epsilon);
 	}
-	
+
 	/**
 	 * Takes the hash code of doubles. Values that are equal according to
 	 * {@link #equals(double, double)} will have the same hash code.
@@ -247,10 +247,10 @@ public final class DecimalComparison {
 	public static final int hash(final double d) {
 		return Float.hashCode((float) d);
 	}
-	
+
 	// You may NOT get any DecimalComparison instances
 	private DecimalComparison() {
 		throw new AssertionError();
 	}
-	
+
 }
diff --git a/src/main/java/sevenUnits/utils/ExpressionParser.java b/src/main/java/sevenUnits/utils/ExpressionParser.java
index 941c2a4..e248ff0 100644
--- a/src/main/java/sevenUnits/utils/ExpressionParser.java
+++ b/src/main/java/sevenUnits/utils/ExpressionParser.java
@@ -1,5 +1,5 @@
 /**
- * Copyright (C) 2019 Adrien Hopkins
+ * Copyright (C) 2019, 2024 Adrien Hopkins
  *
  * This program is free software: you can redistribute it and/or modify
  * it under the terms of the GNU Affero General Public License as published by
@@ -24,6 +24,7 @@ import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
 import java.util.Objects;
+import java.util.function.BiFunction;
 import java.util.function.BinaryOperator;
 import java.util.function.Function;
 import java.util.function.UnaryOperator;
@@ -55,7 +56,7 @@ public final class ExpressionParser<T> {
 		 * @since v0.2.0
 		 */
 		private final Function<String, ? extends T> objectObtainer;
-		
+
 		/**
 		 * The function of the space as an operator (like 3 x y)
 		 * 
@@ -63,7 +64,7 @@ public final class ExpressionParser<T> {
 		 * @since v0.2.0
 		 */
 		private String spaceFunction = null;
-		
+
 		/**
 		 * A map mapping operator strings to operator functions, for unary
 		 * operators.
@@ -72,7 +73,7 @@ public final class ExpressionParser<T> {
 		 * @since v0.2.0
 		 */
 		private final Map<String, PriorityUnaryOperator<T>> unaryOperators;
-		
+
 		/**
 		 * A map mapping operator strings to operator functions, for binary
 		 * operators.
@@ -81,7 +82,14 @@ public final class ExpressionParser<T> {
 		 * @since v0.2.0
 		 */
 		private final Map<String, PriorityBinaryOperator<T>> binaryOperators;
-		
+
+		/**
+		 * A map mapping operator strings to numeric functions.
+		 * 
+		 * @since 2024-03-23
+		 */
+		private final Map<String, PriorityBiFunction<T, UncertainDouble, T>> numericOperators;
+
 		/**
 		 * Creates the {@code Builder}.
 		 * 
@@ -96,8 +104,9 @@ public final class ExpressionParser<T> {
 					"objectObtainer must not be null.");
 			this.unaryOperators = new HashMap<>();
 			this.binaryOperators = new HashMap<>();
+			this.numericOperators = new HashMap<>();
 		}
-		
+
 		/**
 		 * Adds a binary operator to the builder.
 		 * 
@@ -115,7 +124,7 @@ public final class ExpressionParser<T> {
 				final BinaryOperator<T> operator, final int priority) {
 			Objects.requireNonNull(text, "text must not be null.");
 			Objects.requireNonNull(operator, "operator must not be null.");
-			
+
 			// Unfortunately, I cannot use a lambda because the
 			// PriorityBinaryOperator requires arguments.
 			final PriorityBinaryOperator<T> priorityOperator = new PriorityBinaryOperator<>(
@@ -124,12 +133,42 @@ public final class ExpressionParser<T> {
 				public T apply(final T t, final T u) {
 					return operator.apply(t, u);
 				}
-				
+
 			};
 			this.binaryOperators.put(text, priorityOperator);
 			return this;
 		}
-		
+
+		/**
+		 * Adds a two-argument operator where the second operator is a number.
+		 * This is used for operations like vector scaling and exponentation.
+		 * 
+		 * @param text     text used to reference the operator, like '^'
+		 * @param operator operator to add
+		 * @param priority operator's priority, which determines which operators
+		 *                 are applied first
+		 * @return this builder
+		 */
+		public Builder<T> addNumericOperator(final String text,
+				final BiFunction<T, UncertainDouble, T> operator,
+				final int priority) {
+			Objects.requireNonNull(text, "text must not be null.");
+			Objects.requireNonNull(operator, "operator must not be null.");
+
+			// Unfortunately, I cannot use a lambda because the
+			// PriorityBinaryOperator requires arguments.
+			final PriorityBiFunction<T, UncertainDouble, T> priorityOperator = new PriorityBiFunction<>(
+					priority) {
+				@Override
+				public T apply(final T t, final UncertainDouble u) {
+					return operator.apply(t, u);
+				}
+
+			};
+			this.numericOperators.put(text, priorityOperator);
+			return this;
+		}
+
 		/**
 		 * Adds a function for spaces. You must use the text of an existing binary
 		 * operator.
@@ -141,15 +180,15 @@ public final class ExpressionParser<T> {
 		 */
 		public Builder<T> addSpaceFunction(final String operator) {
 			Objects.requireNonNull(operator, "operator must not be null.");
-			
+
 			if (!this.binaryOperators.containsKey(operator))
 				throw new IllegalArgumentException(String
 						.format("Could not find binary operator '%s'", operator));
-			
+
 			this.spaceFunction = operator;
 			return this;
 		}
-		
+
 		/**
 		 * Adds a unary operator to the builder.
 		 * 
@@ -167,7 +206,7 @@ public final class ExpressionParser<T> {
 				final UnaryOperator<T> operator, final int priority) {
 			Objects.requireNonNull(text, "text must not be null.");
 			Objects.requireNonNull(operator, "operator must not be null.");
-			
+
 			// Unfortunately, I cannot use a lambda because the
 			// PriorityUnaryOperator requires arguments.
 			final PriorityUnaryOperator<T> priorityOperator = new PriorityUnaryOperator<>(
@@ -180,7 +219,7 @@ public final class ExpressionParser<T> {
 			this.unaryOperators.put(text, priorityOperator);
 			return this;
 		}
-		
+
 		/**
 		 * @return an {@code ExpressionParser<T>} instance with the properties
 		 *         given to this builder
@@ -189,10 +228,10 @@ public final class ExpressionParser<T> {
 		 */
 		public ExpressionParser<T> build() {
 			return new ExpressionParser<>(this.objectObtainer, this.unaryOperators,
-					this.binaryOperators, this.spaceFunction);
+					this.binaryOperators, this.numericOperators, this.spaceFunction);
 		}
 	}
-	
+
 	/**
 	 * A binary operator with a priority field that determines which operators
 	 * apply first.
@@ -212,7 +251,7 @@ public final class ExpressionParser<T> {
 		 * @since v0.2.0
 		 */
 		private final int priority;
-		
+
 		/**
 		 * Creates the {@code PriorityBinaryOperator}.
 		 * 
@@ -223,7 +262,7 @@ public final class ExpressionParser<T> {
 		public PriorityBinaryOperator(final int priority) {
 			this.priority = priority;
 		}
-		
+
 		/**
 		 * Compares this object to another by priority.
 		 * 
@@ -243,7 +282,68 @@ public final class ExpressionParser<T> {
 			else
 				return 0;
 		}
-		
+
+		/**
+		 * @return priority
+		 * @since 2019-03-22
+		 * @since v0.2.0
+		 */
+		public final int getPriority() {
+			return this.priority;
+		}
+	}
+
+	/**
+	 * A binary operator with a priority field that determines which operators
+	 * apply first.
+	 * 
+	 * @author Adrien Hopkins
+	 * @param <T> type of operand and result
+	 * @since 2019-03-17
+	 * @since v0.2.0
+	 */
+	private static abstract class PriorityBiFunction<T, U, R> implements
+			BiFunction<T, U, R>, Comparable<PriorityBiFunction<T, U, R>> {
+		/**
+		 * The operator's priority. Higher-priority operators are applied before
+		 * lower-priority operators
+		 * 
+		 * @since 2019-03-17
+		 * @since v0.2.0
+		 */
+		private final int priority;
+
+		/**
+		 * Creates the {@code PriorityBinaryOperator}.
+		 * 
+		 * @param priority operator's priority
+		 * @since 2019-03-17
+		 * @since v0.2.0
+		 */
+		public PriorityBiFunction(final int priority) {
+			this.priority = priority;
+		}
+
+		/**
+		 * Compares this object to another by priority.
+		 * 
+		 * <p>
+		 * {@inheritDoc}
+		 * </p>
+		 * 
+		 * @since 2019-03-17
+		 * @since v0.2.0
+		 */
+		@Override
+		public int compareTo(final PriorityBiFunction<T, U, R> o) {
+			if (this.priority < o.priority)
+				return -1;
+			else if (this.priority > o.priority)
+				return 1;
+			else
+				return 0;
+		}
+
 		/**
 		 * @return priority
 		 * @since 2019-03-22
@@ -253,7 +353,7 @@ public final class ExpressionParser<T> {
 			return this.priority;
 		}
 	}
-	
+
 	/**
 	 * A unary operator with a priority field that determines which operators
 	 * apply first.
@@ -273,7 +373,7 @@ public final class ExpressionParser<T> {
 		 * @since v0.2.0
 		 */
 		private final int priority;
-		
+
 		/**
 		 * Creates the {@code PriorityUnaryOperator}.
 		 * 
@@ -284,7 +384,7 @@ public final class ExpressionParser<T> {
 		public PriorityUnaryOperator(final int priority) {
 			this.priority = priority;
 		}
-		
+
 		/**
 		 * Compares this object to another by priority.
 		 * 
@@ -304,7 +404,7 @@ public final class ExpressionParser<T> {
 			else
 				return 0;
 		}
-		
+
 		/**
 		 * @return priority
 		 * @since 2019-03-22
@@ -314,7 +414,7 @@ public final class ExpressionParser<T> {
 			return this.priority;
 		}
 	}
-	
+
 	/**
 	 * The types of tokens that are available.
 	 * 
@@ -323,9 +423,9 @@ public final class ExpressionParser<T> {
 	 * @since v0.2.0
 	 */
 	private static enum TokenType {
-		OBJECT, UNARY_OPERATOR, BINARY_OPERATOR;
+		OBJECT, UNARY_OPERATOR, BINARY_OPERATOR, NUMERIC_OPERATOR;
 	}
-	
+
 	/**
 	 * The opening bracket.
 	 * 
@@ -333,7 +433,7 @@ public final class ExpressionParser<T> {
 	 * @since v0.2.0
 	 */
 	public static final char OPENING_BRACKET = '(';
-	
+
 	/**
 	 * The closing bracket.
 	 * 
@@ -341,7 +441,7 @@ public final class ExpressionParser<T> {
 	 * @since v0.2.0
 	 */
 	public static final char CLOSING_BRACKET = ')';
-	
+
 	/**
 	 * Finds the other bracket in a pair of brackets, given the position of one.
 	 * 
@@ -355,9 +455,9 @@ public final class ExpressionParser<T> {
 	private static int findBracketPair(final String string,
 			final int bracketPosition) {
 		Objects.requireNonNull(string, "string must not be null.");
-		
+
 		final char openingBracket = string.charAt(bracketPosition);
-		
+
 		// figure out what closing bracket to look for
 		final char closingBracket;
 		switch (openingBracket) {
@@ -374,16 +474,16 @@ public final class ExpressionParser<T> {
 			throw new IllegalArgumentException(
 					String.format("Invalid bracket '%s'", openingBracket));
 		}
-		
+
 		// level of brackets. every opening bracket increments this; every closing
 		// bracket decrements it
 		int bracketLevel = 0;
-		
+
 		// iterate over the string to find the closing bracket
 		for (int currentPosition = bracketPosition; currentPosition < string
 				.length(); currentPosition++) {
 			final char currentCharacter = string.charAt(currentPosition);
-			
+
 			if (currentCharacter == openingBracket) {
 				bracketLevel++;
 			} else if (currentCharacter == closingBracket) {
@@ -392,10 +492,10 @@ public final class ExpressionParser<T> {
 					return currentPosition;
 			}
 		}
-		
+
 		throw new IllegalArgumentException("No matching bracket found.");
 	}
-	
+
 	/**
 	 * A function that obtains a parseable object from a string. For example, an
 	 * integer {@code ExpressionParser} would use {@code Integer::parseInt}.
@@ -404,7 +504,7 @@ public final class ExpressionParser<T> {
 	 * @since v0.2.0
 	 */
 	private final Function<String, ? extends T> objectObtainer;
-	
+
 	/**
 	 * A map mapping operator strings to operator functions, for unary operators.
 	 * 
@@ -412,7 +512,7 @@ public final class ExpressionParser<T> {
 	 * @since v0.2.0
 	 */
 	private final Map<String, PriorityUnaryOperator<T>> unaryOperators;
-	
+
 	/**
 	 * A map mapping operator strings to operator functions, for binary
 	 * operators.
@@ -421,7 +521,14 @@ public final class ExpressionParser<T> {
 	 * @since v0.2.0
 	 */
 	private final Map<String, PriorityBinaryOperator<T>> binaryOperators;
-	
+
+	/**
+	 * A map mapping operator strings to numeric functions.
+	 * 
+	 * @since 2024-03-23
+	 */
+	private final Map<String, PriorityBiFunction<T, UncertainDouble, T>> numericOperators;
+
 	/**
 	 * The operator for space, or null if spaces have no function.
 	 * 
@@ -429,27 +536,30 @@ public final class ExpressionParser<T> {
 	 * @since v0.2.0
 	 */
 	private final String spaceOperator;
-	
+
 	/**
 	 * Creates the {@code ExpressionParser}.
 	 * 
-	 * @param objectObtainer  function to get objects from strings
-	 * @param unaryOperators  unary operators available to the parser
-	 * @param binaryOperators binary operators available to the parser
-	 * @param spaceOperator   operator used by spaces
+	 * @param objectObtainer   function to get objects from strings
+	 * @param unaryOperators   unary operators available to the parser
+	 * @param binaryOperators  binary operators available to the parser
+	 * @param numericOperators numeric operators available to the parser
+	 * @param spaceOperator    operator used by spaces
 	 * @since 2019-03-14
 	 * @since v0.2.0
 	 */
 	private ExpressionParser(final Function<String, ? extends T> objectObtainer,
 			final Map<String, PriorityUnaryOperator<T>> unaryOperators,
 			final Map<String, PriorityBinaryOperator<T>> binaryOperators,
+			final Map<String, PriorityBiFunction<T, UncertainDouble, T>> numericOperators,
 			final String spaceOperator) {
 		this.objectObtainer = objectObtainer;
 		this.unaryOperators = unaryOperators;
 		this.binaryOperators = binaryOperators;
+		this.numericOperators = numericOperators;
 		this.spaceOperator = spaceOperator;
 	}
-	
+
 	/**
 	 * Converts a given mathematical expression to reverse Polish notation
 	 * (operators after operands).
@@ -468,19 +578,19 @@ public final class ExpressionParser<T> {
 	 */
 	String convertExpressionToReversePolish(final String expression) {
 		Objects.requireNonNull(expression, "expression must not be null.");
-		
+
 		final List<String> components = new ArrayList<>();
-		
+
 		// the part of the expression remaining to parse
 		String partialExpression = expression;
-		
+
 		// find and deal with brackets
 		while (partialExpression.indexOf(OPENING_BRACKET) != -1) {
 			final int openingBracketPosition = partialExpression
 					.indexOf(OPENING_BRACKET);
 			final int closingBracketPosition = findBracketPair(partialExpression,
 					openingBracketPosition);
-			
+
 			// check for function
 			if (openingBracketPosition > 0
 					&& partialExpression.charAt(openingBracketPosition - 1) != ' ') {
@@ -510,15 +620,15 @@ public final class ExpressionParser<T> {
 						.substring(closingBracketPosition + 1);
 			}
 		}
-		
+
 		// add everything else
 		components.addAll(Arrays.asList(partialExpression.split(" ")));
-		
+
 		// remove empty entries
 		while (components.contains("")) {
 			components.remove("");
 		}
-		
+
 		// deal with space multiplication (x y)
 		if (this.spaceOperator != null) {
 			for (int i = 0; i < components.size() - 1; i++) {
@@ -528,7 +638,7 @@ public final class ExpressionParser<T> {
 				}
 			}
 		}
-		
+
 		// turn the expression into reverse Polish
 		while (true) {
 			final int highestPriorityOperatorPosition = this
@@ -536,7 +646,7 @@ public final class ExpressionParser<T> {
 			if (highestPriorityOperatorPosition == -1) {
 				break;
 			}
-			
+
 			// swap components based on what kind of operator there is
 			// 1 + 2 becomes 2 1 +
 			// - 1 becomes 1 -
@@ -554,6 +664,7 @@ public final class ExpressionParser<T> {
 						operand + " " + unaryOperator);
 				break;
 			case BINARY_OPERATOR:
+			case NUMERIC_OPERATOR:
 				if (components.size() < 3)
 					throw new IllegalArgumentException(
 							"Invalid expression \"" + expression + "\"");
@@ -570,11 +681,11 @@ public final class ExpressionParser<T> {
 				throw new AssertionError("Expected operator, found non-operator.");
 			}
 		}
-		
+
 		// join all of the components together, then ensure there is only one
 		// space in a row
 		String expressionRPN = String.join(" ", components).replaceAll(" +", " ");
-		
+
 		while (expressionRPN.charAt(0) == ' ') {
 			expressionRPN = expressionRPN.substring(1);
 		}
@@ -583,7 +694,7 @@ public final class ExpressionParser<T> {
 		}
 		return expressionRPN;
 	}
-	
+
 	/**
 	 * Finds the position of the highest-priority operator in a list
 	 * 
@@ -601,18 +712,18 @@ public final class ExpressionParser<T> {
 		// find highest priority
 		int maxPriority = Integer.MIN_VALUE;
 		int maxPriorityPosition = -1;
-		
+
 		// go over components one by one
 		// if it is an operator, test its priority to see if it's max
 		// if it is, update maxPriority and maxPriorityPosition
 		for (int i = 0; i < components.size(); i++) {
-			
+
 			switch (this.getTokenType(components.get(i))) {
 			case UNARY_OPERATOR:
 				final PriorityUnaryOperator<T> unaryOperator = this.unaryOperators
 						.get(components.get(i));
 				final int unaryPriority = unaryOperator.getPriority();
-				
+
 				if (unaryPriority > maxPriority) {
 					maxPriority = unaryPriority;
 					maxPriorityPosition = i;
@@ -622,21 +733,31 @@ public final class ExpressionParser<T> {
 				final PriorityBinaryOperator<T> binaryOperator = this.binaryOperators
 						.get(components.get(i));
 				final int binaryPriority = binaryOperator.getPriority();
-				
+
 				if (binaryPriority > maxPriority) {
 					maxPriority = binaryPriority;
 					maxPriorityPosition = i;
 				}
 				break;
+			case NUMERIC_OPERATOR:
+				final PriorityBiFunction<T, UncertainDouble, T> numericOperator = this.numericOperators
+						.get(components.get(i));
+				final int numericPriority = numericOperator.getPriority();
+
+				if (numericPriority > maxPriority) {
+					maxPriority = numericPriority;
+					maxPriorityPosition = i;
+				}
+				break;
 			default:
 				break;
 			}
 		}
-		
+
 		// max priority position found
 		return maxPriorityPosition;
 	}
-	
+
 	/**
 	 * Determines whether an inputted string is an object or an operator
 	 * 
@@ -648,15 +769,17 @@ public final class ExpressionParser<T> {
 	 */
 	private TokenType getTokenType(final String token) {
 		Objects.requireNonNull(token, "token must not be null.");
-		
+
 		if (this.unaryOperators.containsKey(token))
 			return TokenType.UNARY_OPERATOR;
 		else if (this.binaryOperators.containsKey(token))
 			return TokenType.BINARY_OPERATOR;
+		else if (this.numericOperators.containsKey(token))
+			return TokenType.NUMERIC_OPERATOR;
 		else
 			return TokenType.OBJECT;
 	}
-	
+
 	/**
 	 * Parses an expression.
 	 * 
@@ -670,7 +793,7 @@ public final class ExpressionParser<T> {
 		return this.parseReversePolishExpression(
 				this.convertExpressionToReversePolish(expression));
 	}
-	
+
 	/**
 	 * Parses an expression expressed in reverse Polish notation.
 	 * 
@@ -682,55 +805,86 @@ public final class ExpressionParser<T> {
 	 */
 	T parseReversePolishExpression(final String expression) {
 		Objects.requireNonNull(expression, "expression must not be null.");
-		
+
 		final Deque<T> stack = new ArrayDeque<>();
-		
+		final Deque<UncertainDouble> doubleStack = new ArrayDeque<>();
+
 		// iterate over every item in the expression, then
 		for (final String item : expression.split(" ")) {
 			// choose a path based on what kind of thing was just read
 			switch (this.getTokenType(item)) {
-			
+
 			case BINARY_OPERATOR:
 				if (stack.size() < 2)
 					throw new IllegalStateException(String.format(
 							"Attempted to call binary operator %s with only %d arguments.",
 							item, stack.size()));
-				
+
 				// get two arguments and operator, then apply!
 				final T o1 = stack.pop();
 				final T o2 = stack.pop();
 				final BinaryOperator<T> binaryOperator = this.binaryOperators
 						.get(item);
-				
+
 				stack.push(binaryOperator.apply(o1, o2));
 				break;
-			
+
+			case NUMERIC_OPERATOR:
+				if (stack.size() < 1 || doubleStack.size() < 1)
+					throw new IllegalStateException(String.format(
+							"Attempted to call binary operator %s with insufficient arguments.",
+							item));
+
+				final T ot = stack.pop();
+				final UncertainDouble on = doubleStack.pop();
+				final BiFunction<T, UncertainDouble, T> op = this.numericOperators
+						.get(item);
+				stack.push(op.apply(ot, on));
+				break;
+
 			case OBJECT:
 				// just add it to the stack
-				stack.push(this.objectObtainer.apply(item));
+				// these try-catch statements are necessary
+				// to make the code as generalizable as possible
+				// also they're required for number formatting code because
+				// that's the only way to tell if an expression is a number or not.
+				try {
+					stack.push(this.objectObtainer.apply(item));
+				} catch (Exception e) {
+					try {
+						doubleStack.push(UncertainDouble.fromString(item));
+					} catch (IllegalArgumentException e2) {
+						try {
+							doubleStack.push(
+									UncertainDouble.of(Double.parseDouble(item), 0));
+						} catch (NumberFormatException e3) {
+							throw e;
+						}
+					}
+				}
 				break;
-			
+
 			case UNARY_OPERATOR:
 				if (stack.size() < 1)
 					throw new IllegalStateException(String.format(
 							"Attempted to call unary operator %s with only %d arguments.",
 							item, stack.size()));
-				
+
 				// get one argument and operator, then apply!
 				final T o = stack.pop();
 				final UnaryOperator<T> unaryOperator = this.unaryOperators
 						.get(item);
-				
+
 				stack.push(unaryOperator.apply(o));
 				break;
 			default:
 				throw new AssertionError(
 						String.format("Internal error: Invalid token type %s.",
 								this.getTokenType(item)));
-			
+
 			}
 		}
-		
+
 		// return answer, or throw an exception if I can't
 		if (stack.size() > 1)
 			throw new IllegalStateException(
diff --git a/src/main/java/sevenUnits/utils/NameSymbol.java b/src/main/java/sevenUnits/utils/NameSymbol.java
index 9388f63..49c44fa 100644
--- a/src/main/java/sevenUnits/utils/NameSymbol.java
+++ b/src/main/java/sevenUnits/utils/NameSymbol.java
@@ -33,7 +33,7 @@ import java.util.Set;
 public final class NameSymbol {
 	public static final NameSymbol EMPTY = new NameSymbol(Optional.empty(),
 			Optional.empty(), new HashSet<>());
-	
+
 	/**
 	 * Creates a {@code NameSymbol}, ensuring that if primaryName is null and
 	 * otherNames is not empty, one name is moved from otherNames to primaryName
@@ -43,7 +43,7 @@ public final class NameSymbol {
 	private static final NameSymbol create(final String name,
 			final String symbol, final Set<String> otherNames) {
 		final Optional<String> primaryName;
-		
+
 		if (name == null && !otherNames.isEmpty()) {
 			// get primary name and remove it from savedNames
 			final Iterator<String> it = otherNames.iterator();
@@ -53,11 +53,11 @@ public final class NameSymbol {
 		} else {
 			primaryName = Optional.ofNullable(name);
 		}
-		
+
 		return new NameSymbol(primaryName, Optional.ofNullable(symbol),
 				otherNames);
 	}
-	
+
 	/**
 	 * Gets a {@code NameSymbol} with a primary name, a symbol and no other
 	 * names.
@@ -72,7 +72,7 @@ public final class NameSymbol {
 		return new NameSymbol(Optional.of(name), Optional.of(symbol),
 				new HashSet<>());
 	}
-	
+
 	/**
 	 * Gets a {@code NameSymbol} with a primary name, a symbol and additional
 	 * names.
@@ -90,7 +90,7 @@ public final class NameSymbol {
 				new HashSet<>(Objects.requireNonNull(otherNames,
 						"otherNames must not be null.")));
 	}
-	
+
 	/**
 	 * h * Gets a {@code NameSymbol} with a primary name, a symbol and additional
 	 * names.
@@ -108,7 +108,7 @@ public final class NameSymbol {
 				new HashSet<>(Arrays.asList(Objects.requireNonNull(otherNames,
 						"otherNames must not be null."))));
 	}
-	
+
 	/**
 	 * Gets a {@code NameSymbol} with a primary name, no symbol, and no other
 	 * names.
@@ -122,7 +122,7 @@ public final class NameSymbol {
 		return new NameSymbol(Optional.of(name), Optional.empty(),
 				new HashSet<>());
 	}
-	
+
 	/**
 	 * Gets a {@code NameSymbol} with a primary name, a symbol and additional
 	 * names.
@@ -145,7 +145,7 @@ public final class NameSymbol {
 		return NameSymbol.create(name, symbol,
 				otherNames == null ? new HashSet<>() : new HashSet<>(otherNames));
 	}
-	
+
 	/**
 	 * h * Gets a {@code NameSymbol} with a primary name, a symbol and additional
 	 * names.
@@ -168,7 +168,7 @@ public final class NameSymbol {
 		return create(name, symbol, otherNames == null ? new HashSet<>()
 				: new HashSet<>(Arrays.asList(otherNames)));
 	}
-	
+
 	/**
 	 * Gets a {@code NameSymbol} with a symbol and no names.
 	 * 
@@ -181,12 +181,12 @@ public final class NameSymbol {
 		return new NameSymbol(Optional.empty(), Optional.of(symbol),
 				new HashSet<>());
 	}
-	
+
 	private final Optional<String> primaryName;
 	private final Optional<String> symbol;
-	
+
 	private final Set<String> otherNames;
-	
+
 	/**
 	 * Creates the {@code NameSymbol}.
 	 * 
@@ -202,12 +202,12 @@ public final class NameSymbol {
 		this.symbol = symbol;
 		otherNames.remove(null);
 		this.otherNames = Collections.unmodifiableSet(otherNames);
-		
+
 		if (this.primaryName.isEmpty()) {
 			assert this.otherNames.isEmpty();
 		}
 	}
-	
+
 	@Override
 	public boolean equals(Object obj) {
 		if (this == obj)
@@ -232,7 +232,7 @@ public final class NameSymbol {
 			return false;
 		return true;
 	}
-	
+
 	/**
 	 * @return otherNames
 	 * @since 2019-10-21
@@ -240,7 +240,7 @@ public final class NameSymbol {
 	public final Set<String> getOtherNames() {
 		return this.otherNames;
 	}
-	
+
 	/**
 	 * @return primaryName
 	 * @since 2019-10-21
@@ -248,7 +248,7 @@ public final class NameSymbol {
 	public final Optional<String> getPrimaryName() {
 		return this.primaryName;
 	}
-	
+
 	/**
 	 * @return symbol
 	 * @since 2019-10-21
@@ -256,7 +256,7 @@ public final class NameSymbol {
 	public final Optional<String> getSymbol() {
 		return this.symbol;
 	}
-	
+
 	@Override
 	public int hashCode() {
 		final int prime = 31;
@@ -269,7 +269,7 @@ public final class NameSymbol {
 				+ (this.symbol == null ? 0 : this.symbol.hashCode());
 		return result;
 	}
-	
+
 	/**
 	 * @return true iff this {@code NameSymbol} contains no names or symbols.
 	 */
@@ -277,7 +277,7 @@ public final class NameSymbol {
 		// if primaryName is empty, otherNames must also be empty
 		return this.primaryName.isEmpty() && this.symbol.isEmpty();
 	}
-	
+
 	@Override
 	public String toString() {
 		if (this.isEmpty())
@@ -288,7 +288,7 @@ public final class NameSymbol {
 		else
 			return this.primaryName.orElseGet(this.symbol::orElseThrow);
 	}
-	
+
 	/**
 	 * Creates and returns a copy of this {@code NameSymbol} with the provided
 	 * extra name. If this {@code NameSymbol} has a primary name, the provided
diff --git a/src/main/java/sevenUnits/utils/Nameable.java b/src/main/java/sevenUnits/utils/Nameable.java
index e469d04..3959a64 100644
--- a/src/main/java/sevenUnits/utils/Nameable.java
+++ b/src/main/java/sevenUnits/utils/Nameable.java
@@ -35,14 +35,14 @@ public interface Nameable {
 		final NameSymbol ns = this.getNameSymbol();
 		return ns.getPrimaryName().or(ns::getSymbol).orElse("Unnamed");
 	}
-	
+
 	/**
 	 * @return a {@code NameSymbol} that contains this object's primary name,
 	 *         symbol and other names
 	 * @since 2020-09-07
 	 */
 	NameSymbol getNameSymbol();
-	
+
 	/**
 	 * @return set of alternate names
 	 * @since 2020-09-07
@@ -50,7 +50,7 @@ public interface Nameable {
 	default Set<String> getOtherNames() {
 		return this.getNameSymbol().getOtherNames();
 	}
-	
+
 	/**
 	 * @return preferred name of object
 	 * @since 2020-09-07
@@ -58,7 +58,7 @@ public interface Nameable {
 	default Optional<String> getPrimaryName() {
 		return this.getNameSymbol().getPrimaryName();
 	}
-	
+
 	/**
 	 * @return a short name for the object - if there's a symbol, it's that,
 	 *         otherwise the symbol, otherwise "Unnamed"
@@ -68,7 +68,7 @@ public interface Nameable {
 		final NameSymbol ns = this.getNameSymbol();
 		return ns.getSymbol().or(ns::getPrimaryName).orElse("Unnamed");
 	}
-	
+
 	/**
 	 * @return short symbol representing object
 	 * @since 2020-09-07
diff --git a/src/main/java/sevenUnits/utils/ObjectProduct.java b/src/main/java/sevenUnits/utils/ObjectProduct.java
index 66bb773..5a29d79 100644
--- a/src/main/java/sevenUnits/utils/ObjectProduct.java
+++ b/src/main/java/sevenUnits/utils/ObjectProduct.java
@@ -44,7 +44,7 @@ public class ObjectProduct<T> implements Nameable {
 	public static final <T> ObjectProduct<T> empty() {
 		return new ObjectProduct<>(new HashMap<>());
 	}
-	
+
 	/**
 	 * Gets an {@code ObjectProduct} from an object-to-integer mapping
 	 * 
@@ -57,7 +57,7 @@ public class ObjectProduct<T> implements Nameable {
 			final Map<T, Integer> map) {
 		return new ObjectProduct<>(new HashMap<>(map));
 	}
-	
+
 	/**
 	 * Gets an ObjectProduct that has one of the inputted argument, and nothing
 	 * else.
@@ -73,7 +73,7 @@ public class ObjectProduct<T> implements Nameable {
 		map.put(object, 1);
 		return new ObjectProduct<>(map);
 	}
-	
+
 	/**
 	 * The objects that make up the product, mapped to their exponents. This map
 	 * treats zero as null, and is immutable.
@@ -81,12 +81,12 @@ public class ObjectProduct<T> implements Nameable {
 	 * @since 2019-10-16
 	 */
 	final Map<T, Integer> exponents;
-	
+
 	/**
 	 * The object's name and symbol
 	 */
 	private final NameSymbol nameSymbol;
-	
+
 	/**
 	 * Creates a {@code ObjectProduct} without a name/symbol.
 	 * 
@@ -96,7 +96,7 @@ public class ObjectProduct<T> implements Nameable {
 	ObjectProduct(final Map<T, Integer> exponents) {
 		this(exponents, NameSymbol.EMPTY);
 	}
-	
+
 	/**
 	 * Creates the {@code ObjectProduct}.
 	 * 
@@ -110,7 +110,7 @@ public class ObjectProduct<T> implements Nameable {
 						e -> !Integer.valueOf(0).equals(e.getValue())));
 		this.nameSymbol = nameSymbol;
 	}
-	
+
 	/**
 	 * Calculates the quotient of two products
 	 *
@@ -125,17 +125,17 @@ public class ObjectProduct<T> implements Nameable {
 		final Set<T> objects = new HashSet<>();
 		objects.addAll(this.getBaseSet());
 		objects.addAll(other.getBaseSet());
-		
+
 		// get a list of all exponents
 		final Map<T, Integer> map = new HashMap<>(objects.size());
 		for (final T key : objects) {
 			map.put(key, this.getExponent(key) - other.getExponent(key));
 		}
-		
+
 		// create the product
 		return new ObjectProduct<>(map);
 	}
-	
+
 	// this method relies on the use of ZeroIsNullMap
 	@Override
 	public boolean equals(final Object obj) {
@@ -146,7 +146,7 @@ public class ObjectProduct<T> implements Nameable {
 		final ObjectProduct<?> other = (ObjectProduct<?>) obj;
 		return Objects.equals(this.exponents, other.exponents);
 	}
-	
+
 	/**
 	 * @return immutable map mapping objects to exponents
 	 * @since 2019-10-16
@@ -154,7 +154,7 @@ public class ObjectProduct<T> implements Nameable {
 	public Map<T, Integer> exponentMap() {
 		return this.exponents;
 	}
-	
+
 	/**
 	 * @return a set of all of the base objects with non-zero exponents that make
 	 *         up this dimension.
@@ -163,7 +163,7 @@ public class ObjectProduct<T> implements Nameable {
 	 */
 	public final Set<T> getBaseSet() {
 		final Set<T> dimensions = new HashSet<>();
-		
+
 		// add all dimensions with a nonzero exponent - zero exponents shouldn't
 		// be there in the first place
 		for (final T dimension : this.exponents.keySet()) {
@@ -171,10 +171,10 @@ public class ObjectProduct<T> implements Nameable {
 				dimensions.add(dimension);
 			}
 		}
-		
+
 		return dimensions;
 	}
-	
+
 	/**
 	 * Gets the exponent for a specific dimension.
 	 * 
@@ -186,17 +186,17 @@ public class ObjectProduct<T> implements Nameable {
 	public int getExponent(final T dimension) {
 		return this.exponents.getOrDefault(dimension, 0);
 	}
-	
+
 	@Override
 	public NameSymbol getNameSymbol() {
 		return this.nameSymbol;
 	}
-	
+
 	@Override
 	public int hashCode() {
 		return Objects.hash(this.exponents);
 	}
-	
+
 	/**
 	 * @return true if this product is a single object, i.e. it has one exponent
 	 *         of one and no other nonzero exponents
@@ -214,7 +214,7 @@ public class ObjectProduct<T> implements Nameable {
 		}
 		return oneCount == 1 && !twoOrMore;
 	}
-	
+
 	/**
 	 * Multiplies this product by another
 	 *
@@ -229,17 +229,17 @@ public class ObjectProduct<T> implements Nameable {
 		final Set<T> objects = new HashSet<>();
 		objects.addAll(this.getBaseSet());
 		objects.addAll(other.getBaseSet());
-		
+
 		// get a list of all exponents
 		final Map<T, Integer> map = new HashMap<>(objects.size());
 		for (final T key : objects) {
 			map.put(key, this.getExponent(key) + other.getExponent(key));
 		}
-		
+
 		// create the product
 		return new ObjectProduct<>(map);
 	}
-	
+
 	/**
 	 * Returns this product, but to an exponent
 	 * 
@@ -254,7 +254,7 @@ public class ObjectProduct<T> implements Nameable {
 		}
 		return new ObjectProduct<>(map);
 	}
-	
+
 	/**
 	 * Converts this product to a string using the objects'
 	 * {@link Object#toString()} method (or {@link Nameable#getShortName} if
@@ -271,7 +271,7 @@ public class ObjectProduct<T> implements Nameable {
 				.toString(o -> o instanceof Nameable ? ((Nameable) o).getShortName()
 						: o.toString());
 	}
-	
+
 	/**
 	 * Converts this product to a string. The objects that make up this product
 	 * are represented by {@code objectToString}
@@ -283,7 +283,7 @@ public class ObjectProduct<T> implements Nameable {
 	public String toString(final Function<T, String> objectToString) {
 		final List<String> positiveStringComponents = new ArrayList<>();
 		final List<String> negativeStringComponents = new ArrayList<>();
-		
+
 		// for each base object that makes up this object, add it and its exponent
 		for (final T object : this.getBaseSet()) {
 			final int exponent = this.exponents.get(object);
@@ -297,15 +297,15 @@ public class ObjectProduct<T> implements Nameable {
 						objectToString.apply(object), -exponent));
 			}
 		}
-		
+
 		final String positiveString = positiveStringComponents.isEmpty() ? "1"
 				: String.join(" * ", positiveStringComponents);
 		final String negativeString = negativeStringComponents.isEmpty() ? ""
 				: " / " + String.join(" * ", negativeStringComponents);
-		
+
 		return positiveString + negativeString;
 	}
-	
+
 	/**
 	 * @return named version of this {@code ObjectProduct}, using data from
 	 *         {@code nameSymbol}
diff --git a/src/main/java/sevenUnits/utils/SemanticVersionNumber.java b/src/main/java/sevenUnits/utils/SemanticVersionNumber.java
index e80e16e..fc47baa 100644
--- a/src/main/java/sevenUnits/utils/SemanticVersionNumber.java
+++ b/src/main/java/sevenUnits/utils/SemanticVersionNumber.java
@@ -61,7 +61,7 @@ public final class SemanticVersionNumber
 		private final int patch;
 		private final List<String> preReleaseIdentifiers;
 		private final List<String> buildMetadata;
-		
+
 		/**
 		 * Creates a builder which can be used to create a
 		 * {@code SemanticVersionNumber}
@@ -79,7 +79,7 @@ public final class SemanticVersionNumber
 			this.preReleaseIdentifiers = new ArrayList<>();
 			this.buildMetadata = new ArrayList<>();
 		}
-		
+
 		/**
 		 * @return version number created by this builder
 		 * @since v0.4.0
@@ -89,7 +89,7 @@ public final class SemanticVersionNumber
 			return new SemanticVersionNumber(this.major, this.minor, this.patch,
 					this.preReleaseIdentifiers, this.buildMetadata);
 		}
-		
+
 		/**
 		 * Adds one or more build metadata identifiers
 		 *
@@ -109,7 +109,7 @@ public final class SemanticVersionNumber
 			}
 			return this;
 		}
-		
+
 		/**
 		 * Adds one or more build metadata identifiers
 		 *
@@ -129,7 +129,7 @@ public final class SemanticVersionNumber
 			}
 			return this;
 		}
-		
+
 		@Override
 		public boolean equals(Object obj) {
 			if (this == obj)
@@ -142,13 +142,13 @@ public final class SemanticVersionNumber
 					&& this.patch == other.patch && Objects.equals(
 							this.preReleaseIdentifiers, other.preReleaseIdentifiers);
 		}
-		
+
 		@Override
 		public int hashCode() {
 			return Objects.hash(this.buildMetadata, this.major, this.minor,
 					this.patch, this.preReleaseIdentifiers);
 		}
-		
+
 		/**
 		 * Adds one or more numeric identifiers to the version number
 		 *
@@ -167,7 +167,7 @@ public final class SemanticVersionNumber
 			}
 			return this;
 		}
-		
+
 		/**
 		 * Adds one or more pre-release identifier(s) to the version number
 		 *
@@ -187,7 +187,7 @@ public final class SemanticVersionNumber
 			}
 			return this;
 		}
-		
+
 		/**
 		 * Adds one or more pre-release identifier(s) to the version number
 		 *
@@ -207,7 +207,7 @@ public final class SemanticVersionNumber
 			}
 			return this;
 		}
-		
+
 		/**
 		 * Adds a string identifier and an integer identifer to pre-release data
 		 *
@@ -229,13 +229,13 @@ public final class SemanticVersionNumber
 			this.preReleaseIdentifiers.add(Integer.toString(identifier2));
 			return this;
 		}
-		
+
 		@Override
 		public String toString() {
 			return "Semantic Version Builder: " + this.build().toString();
 		}
 	}
-	
+
 	/**
 	 * An alternative comparison method for version numbers. This uses the
 	 * version's natural order, but the build metadata will be compared (using
@@ -257,21 +257,21 @@ public final class SemanticVersionNumber
 				return naturalComparison;
 		};
 	};
-	
+
 	/** The alphanumeric pattern all identifiers must follow */
 	private static final Pattern VALID_IDENTIFIER = Pattern
 			.compile("[0-9A-Za-z-]+");
-	
+
 	/** The numeric pattern which causes special behaviour */
 	private static final Pattern NUMERIC_IDENTIFER = Pattern.compile("[0-9]+");
-	
+
 	/** The pattern for a version number */
 	private static final Pattern VERSION_NUMBER = Pattern
 			.compile("(0|[1-9][0-9]*)\\.(0|[1-9][0-9]*)\\.(0|[1-9][0-9]*)" // main
 					// version
 					+ "(?:-([0-9a-zA-Z-]+(?:\\.[0-9a-zA-Z-]+)*))?" // pre-release
 					+ "(?:\\+([0-9a-zA-Z-]+(?:\\.[0-9a-zA-Z-]+)*))?"); // build data
-	
+
 	/**
 	 * Creates a builder that can be used to create a version number
 	 *
@@ -296,7 +296,7 @@ public final class SemanticVersionNumber
 					"Patch version must be non-negative.");
 		return new SemanticVersionNumber.Builder(major, minor, patch);
 	}
-	
+
 	/**
 	 * Compares two lists of strings based on SemVer's precedence rules
 	 *
@@ -311,24 +311,24 @@ public final class SemanticVersionNumber
 		// test pre-release size
 		final int aSize = a.size();
 		final int bSize = b.size();
-		
+
 		// no identifiers is greater than any identifiers
 		if (aSize != 0 && bSize == 0)
 			return -1;
 		else if (aSize == 0 && bSize != 0)
 			return 1;
-		
+
 		// test identifiers one by one
 		for (int i = 0; i < Math.min(aSize, bSize); i++) {
 			final String aElement = a.get(i);
 			final String bElement = b.get(i);
-			
+
 			if (NUMERIC_IDENTIFER.matcher(aElement).matches()) {
 				if (NUMERIC_IDENTIFER.matcher(bElement).matches()) {
 					// both are numbers, compare them
 					final int aNumber = Integer.parseInt(aElement);
 					final int bNumber = Integer.parseInt(bElement);
-					
+
 					if (aNumber < bNumber)
 						return -1;
 					else if (aNumber > bNumber)
@@ -350,7 +350,7 @@ public final class SemanticVersionNumber
 				}
 			}
 		}
-		
+
 		// we just tested the stuff that's in common, maybe someone has more
 		if (aSize < bSize)
 			return -1;
@@ -359,7 +359,7 @@ public final class SemanticVersionNumber
 		else
 			return 0;
 	}
-	
+
 	/**
 	 * Gets a version number from a string in the official format
 	 *
@@ -377,12 +377,12 @@ public final class SemanticVersionNumber
 			throw new IllegalArgumentException(
 					String.format("Provided string \"%s\" is not a version number",
 							versionString));
-		
+
 		// main parts
 		final int major = Integer.parseInt(m.group(1));
 		final int minor = Integer.parseInt(m.group(2));
 		final int patch = Integer.parseInt(m.group(3));
-		
+
 		// pre release
 		final List<String> preRelease;
 		if (m.group(4) == null) {
@@ -390,7 +390,7 @@ public final class SemanticVersionNumber
 		} else {
 			preRelease = Arrays.asList(m.group(4).split("\\."));
 		}
-		
+
 		// build metadata
 		final List<String> buildMetadata;
 		if (m.group(5) == null) {
@@ -398,12 +398,12 @@ public final class SemanticVersionNumber
 		} else {
 			buildMetadata = Arrays.asList(m.group(5).split("\\."));
 		}
-		
+
 		// return number
 		return new SemanticVersionNumber(major, minor, patch, preRelease,
 				buildMetadata);
 	}
-	
+
 	/**
 	 * Tests whether a string is a valid Semantic Version string
 	 * 
@@ -415,7 +415,7 @@ public final class SemanticVersionNumber
 	public static final boolean isValidVersionString(String versionString) {
 		return VERSION_NUMBER.matcher(versionString).matches();
 	}
-	
+
 	/**
 	 * Creates a simple pre-release version number of the form
 	 * MAJOR.MINOR.PATH-TYPE.NUMBER (e.g. 1.2.3-alpha.4).
@@ -454,7 +454,7 @@ public final class SemanticVersionNumber
 				List.of(preReleaseType, Integer.toString(preReleaseNumber)),
 				List.of());
 	}
-	
+
 	/**
 	 * Creates a {@code SemanticVersionNumber} instance without pre-release
 	 * identifiers or build metadata.
@@ -484,14 +484,14 @@ public final class SemanticVersionNumber
 		return new SemanticVersionNumber(major, minor, patch, List.of(),
 				List.of());
 	}
-	
+
 	// parts of the version number
 	private final int major;
 	private final int minor;
 	private final int patch;
 	private final List<String> preReleaseIdentifiers;
 	private final List<String> buildMetadata;
-	
+
 	/**
 	 * Creates a version number
 	 *
@@ -511,7 +511,7 @@ public final class SemanticVersionNumber
 		this.preReleaseIdentifiers = preReleaseIdentifiers;
 		this.buildMetadata = buildMetadata;
 	}
-	
+
 	/**
 	 * @return build metadata (empty if there is none)
 	 * @since v0.4.0
@@ -520,7 +520,7 @@ public final class SemanticVersionNumber
 	public List<String> buildMetadata() {
 		return Collections.unmodifiableList(this.buildMetadata);
 	}
-	
+
 	/**
 	 * Compares two version numbers according to the official Semantic Versioning
 	 * order.
@@ -538,23 +538,23 @@ public final class SemanticVersionNumber
 			return -1;
 		else if (this.major > o.major)
 			return 1;
-		
+
 		if (this.minor < o.minor)
 			return -1;
 		else if (this.minor > o.minor)
 			return 1;
-		
+
 		if (this.patch < o.patch)
 			return -1;
 		else if (this.patch > o.patch)
 			return 1;
-			
+
 		// now we just compare pre-release identifiers
 		// (remember: build metadata is ignored)
 		return SemanticVersionNumber.compareIdentifiers(
 				this.preReleaseIdentifiers, o.preReleaseIdentifiers);
 	}
-	
+
 	/**
 	 * Determines the compatibility of code written for this version to
 	 * {@code other}. More specifically:
@@ -590,11 +590,11 @@ public final class SemanticVersionNumber
 	 */
 	public boolean compatibleWith(SemanticVersionNumber other) {
 		Objects.requireNonNull(other, "other may not be null");
-		
+
 		return this.compareTo(other) == 0 || this.major != 0
 				&& this.major == other.major && this.compareTo(other) < 0;
 	}
-	
+
 	@Override
 	public boolean equals(Object obj) {
 		if (this == obj)
@@ -621,7 +621,7 @@ public final class SemanticVersionNumber
 			return false;
 		return true;
 	}
-	
+
 	@Override
 	public int hashCode() {
 		final int prime = 31;
@@ -635,7 +635,7 @@ public final class SemanticVersionNumber
 				: this.preReleaseIdentifiers.hashCode());
 		return result;
 	}
-	
+
 	/**
 	 * @return true iff this version is stable (major version > 0 and not a
 	 *         pre-release)
@@ -645,7 +645,7 @@ public final class SemanticVersionNumber
 	public boolean isStable() {
 		return this.major > 0 && this.preReleaseIdentifiers.isEmpty();
 	}
-	
+
 	/**
 	 * @return the MAJOR version number, incremented when you make backwards
 	 *         incompatible API changes
@@ -655,7 +655,7 @@ public final class SemanticVersionNumber
 	public int majorVersion() {
 		return this.major;
 	}
-	
+
 	/**
 	 * @return the MINOR version number, incremented when you add backwards
 	 *         compatible functionality
@@ -665,7 +665,7 @@ public final class SemanticVersionNumber
 	public int minorVersion() {
 		return this.minor;
 	}
-	
+
 	/**
 	 * @return the PATCH version number, incremented when you make backwards
 	 *         compatible bug fixes
@@ -675,7 +675,7 @@ public final class SemanticVersionNumber
 	public int patchVersion() {
 		return this.patch;
 	}
-	
+
 	/**
 	 * @return identifiers describing this pre-release (empty if not a
 	 *         pre-release)
@@ -685,7 +685,7 @@ public final class SemanticVersionNumber
 	public List<String> preReleaseIdentifiers() {
 		return Collections.unmodifiableList(this.preReleaseIdentifiers);
 	}
-	
+
 	/**
 	 * Converts a version number to a string using the official SemVer format.
 	 * The core of a version is MAJOR.MINOR.PATCH, without zero-padding. If
diff --git a/src/main/java/sevenUnits/utils/UncertainDouble.java b/src/main/java/sevenUnits/utils/UncertainDouble.java
index ac523b3..66d8103 100644
--- a/src/main/java/sevenUnits/utils/UncertainDouble.java
+++ b/src/main/java/sevenUnits/utils/UncertainDouble.java
@@ -23,7 +23,7 @@ import java.util.regex.Matcher;
 import java.util.regex.Pattern;
 
 /**
- * A double with an associated uncertainty value. For example, 3.2 ± 0.2.
+ * A double with an associated uncertainty value. For example, 3.2 � 0.2.
  * <p>
  * All methods in this class throw a NullPointerException if any of their
  * arguments is null.
@@ -35,20 +35,20 @@ public final class UncertainDouble implements Comparable<UncertainDouble> {
 	 * The exact value 0
 	 */
 	public static final UncertainDouble ZERO = UncertainDouble.of(0, 0);
-	
+
 	static final String NUMBER_REGEX = "(\\d+(?:[\\.,]\\d+))";
-	
+
 	/**
 	 * A regular expression that can recognize toString forms
 	 */
 	static final Pattern TO_STRING = Pattern.compile(NUMBER_REGEX
-			// optional "± [number]"
-			+ "(?:\\s*(?:±|\\+-)\\s*" + NUMBER_REGEX + ")?");
-	
+			// optional "� [number]"
+			+ "(?:\\s*(?:�|\\+-)\\s*" + NUMBER_REGEX + ")?");
+
 	/**
 	 * Gets an UncertainDouble from a double string. The uncertainty of the
 	 * double will be one of the lowest decimal place of the number. For example,
-	 * "12345.678" will become 12345.678 ± 0.001.
+	 * "12345.678" will become 12345.678 � 0.001.
 	 * 
 	 * @throws NumberFormatException if the argument is not a number
 	 *
@@ -59,13 +59,13 @@ public final class UncertainDouble implements Comparable<UncertainDouble> {
 		final double uncertainty = Math.pow(10, -value.scale());
 		return UncertainDouble.of(value.doubleValue(), uncertainty);
 	}
-	
+
 	/**
 	 * Parses a string in the form of {@link UncertainDouble#toString(boolean)}
 	 * and returns the corresponding {@code UncertainDouble} instance.
 	 * <p>
 	 * This method allows some alternative forms of the string representation,
-	 * such as using "+-" instead of "±".
+	 * such as using "+-" instead of "�".
 	 * 
 	 * @param s string to parse
 	 * @return {@code UncertainDouble} instance
@@ -75,11 +75,11 @@ public final class UncertainDouble implements Comparable<UncertainDouble> {
 	public static final UncertainDouble fromString(String s) {
 		Objects.requireNonNull(s, "s may not be null");
 		final Matcher matcher = TO_STRING.matcher(s);
-		
+
 		if (!matcher.matches())
 			throw new IllegalArgumentException(
 					"Could not parse stirng \"" + s + "\".");
-		
+
 		double value, uncertainty;
 		try {
 			value = Double.parseDouble(matcher.group(1));
@@ -87,7 +87,7 @@ public final class UncertainDouble implements Comparable<UncertainDouble> {
 			throw new IllegalArgumentException(
 					"String " + s + " not in correct format.");
 		}
-		
+
 		final String uncertaintyString = matcher.group(2);
 		if (uncertaintyString == null) {
 			uncertainty = 0;
@@ -99,10 +99,10 @@ public final class UncertainDouble implements Comparable<UncertainDouble> {
 						"String " + s + " not in correct format.");
 			}
 		}
-		
+
 		return UncertainDouble.of(value, uncertainty);
 	}
-	
+
 	/**
 	 * Gets an {@code UncertainDouble} from its value and <b>absolute</b>
 	 * uncertainty.
@@ -112,7 +112,7 @@ public final class UncertainDouble implements Comparable<UncertainDouble> {
 	public static final UncertainDouble of(double value, double uncertainty) {
 		return new UncertainDouble(value, uncertainty);
 	}
-	
+
 	/**
 	 * Gets an {@code UncertainDouble} from its value and <b>relative</b>
 	 * uncertainty.
@@ -123,11 +123,11 @@ public final class UncertainDouble implements Comparable<UncertainDouble> {
 			double relativeUncertainty) {
 		return new UncertainDouble(value, value * relativeUncertainty);
 	}
-	
+
 	private final double value;
-	
+
 	private final double uncertainty;
-	
+
 	/**
 	 * @param value
 	 * @param uncertainty
@@ -138,13 +138,13 @@ public final class UncertainDouble implements Comparable<UncertainDouble> {
 		// uncertainty should only ever be positive
 		this.uncertainty = Math.abs(uncertainty);
 	}
-	
+
 	/**
 	 * Compares this {@code UncertainDouble} with another
 	 * {@code UncertainDouble}.
 	 * <p>
-	 * This method only compares the values, not the uncertainties. So 3.1 ± 0.5
-	 * is considered less than 3.2 ± 0.5, even though they are equivalent.
+	 * This method only compares the values, not the uncertainties. So 3.1 � 0.5
+	 * is considered less than 3.2 � 0.5, even though they are equivalent.
 	 * <p>
 	 * <b>Note:</b> The natural ordering of this class is inconsistent with
 	 * equals. Specifically, if two {@code UncertainDouble} instances {@code a}
@@ -156,7 +156,7 @@ public final class UncertainDouble implements Comparable<UncertainDouble> {
 	public final int compareTo(UncertainDouble o) {
 		return Double.compare(this.value, o.value);
 	}
-	
+
 	/**
 	 * Returns the quotient of {@code this} and {@code other}.
 	 * 
@@ -167,7 +167,7 @@ public final class UncertainDouble implements Comparable<UncertainDouble> {
 		return UncertainDouble.ofRelative(this.value / other.value, Math
 				.hypot(this.relativeUncertainty(), other.relativeUncertainty()));
 	}
-	
+
 	/**
 	 * Returns the quotient of {@code this} and the exact value {@code other}.
 	 * 
@@ -176,7 +176,7 @@ public final class UncertainDouble implements Comparable<UncertainDouble> {
 	public final UncertainDouble dividedByExact(double other) {
 		return UncertainDouble.of(this.value / other, this.uncertainty / other);
 	}
-	
+
 	@Override
 	public final boolean equals(Object obj) {
 		if (this == obj)
@@ -190,7 +190,7 @@ public final class UncertainDouble implements Comparable<UncertainDouble> {
 			return false;
 		return true;
 	}
-	
+
 	/**
 	 * @param other another {@code UncertainDouble}
 	 * @return true iff this and {@code other} are within each other's
@@ -202,7 +202,7 @@ public final class UncertainDouble implements Comparable<UncertainDouble> {
 		return Math.abs(this.value - other.value) <= Math.min(this.uncertainty,
 				other.uncertainty);
 	}
-	
+
 	/**
 	 * Gets the preferred scale for rounding a value for toString.
 	 * 
@@ -217,19 +217,19 @@ public final class UncertainDouble implements Comparable<UncertainDouble> {
 		// the value is rounded to the same number of decimal places as the
 		// uncertainty.
 		final BigDecimal bigUncertainty = BigDecimal.valueOf(this.uncertainty);
-		
+
 		// the scale that will give the uncertainty two decimal places
 		final int twoDecimalPlacesScale = bigUncertainty.scale()
 				- bigUncertainty.precision() + 2;
 		final BigDecimal roundedUncertainty = bigUncertainty
 				.setScale(twoDecimalPlacesScale, RoundingMode.HALF_EVEN);
-		
+
 		if (roundedUncertainty.unscaledValue().intValue() >= 20)
 			return twoDecimalPlacesScale - 1; // one decimal place
 		else
 			return twoDecimalPlacesScale;
 	}
-	
+
 	@Override
 	public final int hashCode() {
 		final int prime = 31;
@@ -238,7 +238,7 @@ public final class UncertainDouble implements Comparable<UncertainDouble> {
 		result = prime * result + Double.hashCode(this.uncertainty);
 		return result;
 	}
-	
+
 	/**
 	 * @return true iff the value has no uncertainty
 	 * 
@@ -247,7 +247,7 @@ public final class UncertainDouble implements Comparable<UncertainDouble> {
 	public final boolean isExact() {
 		return this.uncertainty == 0;
 	}
-	
+
 	/**
 	 * Returns the difference of {@code this} and {@code other}.
 	 * 
@@ -258,7 +258,7 @@ public final class UncertainDouble implements Comparable<UncertainDouble> {
 		return UncertainDouble.of(this.value - other.value,
 				Math.hypot(this.uncertainty, other.uncertainty));
 	}
-	
+
 	/**
 	 * Returns the difference of {@code this} and the exact value {@code other}.
 	 * 
@@ -267,7 +267,7 @@ public final class UncertainDouble implements Comparable<UncertainDouble> {
 	public final UncertainDouble minusExact(double other) {
 		return UncertainDouble.of(this.value - other, this.uncertainty);
 	}
-	
+
 	/**
 	 * Returns the sum of {@code this} and {@code other}.
 	 * 
@@ -278,7 +278,7 @@ public final class UncertainDouble implements Comparable<UncertainDouble> {
 		return UncertainDouble.of(this.value + other.value,
 				Math.hypot(this.uncertainty, other.uncertainty));
 	}
-	
+
 	/**
 	 * Returns the sum of {@code this} and the exact value {@code other}.
 	 * 
@@ -287,7 +287,7 @@ public final class UncertainDouble implements Comparable<UncertainDouble> {
 	public final UncertainDouble plusExact(double other) {
 		return UncertainDouble.of(this.value + other, this.uncertainty);
 	}
-	
+
 	/**
 	 * @return relative uncertainty
 	 * @since 2020-09-07
@@ -295,7 +295,7 @@ public final class UncertainDouble implements Comparable<UncertainDouble> {
 	public final double relativeUncertainty() {
 		return this.uncertainty / this.value;
 	}
-	
+
 	/**
 	 * Returns the product of {@code this} and {@code other}.
 	 * 
@@ -306,7 +306,7 @@ public final class UncertainDouble implements Comparable<UncertainDouble> {
 		return UncertainDouble.ofRelative(this.value * other.value, Math
 				.hypot(this.relativeUncertainty(), other.relativeUncertainty()));
 	}
-	
+
 	/**
 	 * Returns the product of {@code this} and the exact value {@code other}.
 	 * 
@@ -315,7 +315,7 @@ public final class UncertainDouble implements Comparable<UncertainDouble> {
 	public final UncertainDouble timesExact(double other) {
 		return UncertainDouble.of(this.value * other, this.uncertainty * other);
 	}
-	
+
 	/**
 	 * Returns the result of {@code this} raised to the exponent {@code other}.
 	 * 
@@ -323,15 +323,15 @@ public final class UncertainDouble implements Comparable<UncertainDouble> {
 	 */
 	public final UncertainDouble toExponent(UncertainDouble other) {
 		Objects.requireNonNull(other, "other may not be null");
-		
+
 		final double result = Math.pow(this.value, other.value);
 		final double relativeUncertainty = Math.hypot(
 				other.value * this.relativeUncertainty(),
 				Math.log(this.value) * other.uncertainty);
-		
+
 		return UncertainDouble.ofRelative(result, relativeUncertainty);
 	}
-	
+
 	/**
 	 * Returns the result of {@code this} raised the exact exponent
 	 * {@code other}.
@@ -342,7 +342,7 @@ public final class UncertainDouble implements Comparable<UncertainDouble> {
 		return UncertainDouble.ofRelative(Math.pow(this.value, other),
 				this.relativeUncertainty() * other);
 	}
-	
+
 	/**
 	 * Returns a string representation of this {@code UncertainDouble}.
 	 * <p>
@@ -354,8 +354,8 @@ public final class UncertainDouble implements Comparable<UncertainDouble> {
 	 * Examples:
 	 * 
 	 * <pre>
-	 * UncertainDouble.of(3.27, 0.22).toString() = "3.3 ± 0.2"
-	 * UncertainDouble.of(3.27, 0.13).toString() = "3.27 ± 0.13"
+	 * UncertainDouble.of(3.27, 0.22).toString() = "3.3 � 0.2"
+	 * UncertainDouble.of(3.27, 0.13).toString() = "3.27 � 0.13"
 	 * UncertainDouble.of(-5.01, 0).toString() = "-5.01"
 	 * </pre>
 	 * 
@@ -365,12 +365,12 @@ public final class UncertainDouble implements Comparable<UncertainDouble> {
 	public final String toString() {
 		return this.toString(!this.isExact(), RoundingMode.HALF_EVEN);
 	}
-	
+
 	/**
 	 * Returns a string representation of this {@code UncertainDouble}.
 	 * <p>
 	 * If {@code showUncertainty} is true, the string will be of the form "VALUE
-	 * ± UNCERTAINTY", and if it is false the string will be of the form "VALUE"
+	 * � UNCERTAINTY", and if it is false the string will be of the form "VALUE"
 	 * <p>
 	 * VALUE represents a string representation of this {@code UncertainDouble}'s
 	 * value. If the uncertainty is non-zero, the string will be rounded to the
@@ -385,11 +385,11 @@ public final class UncertainDouble implements Comparable<UncertainDouble> {
 	 * 
 	 * <pre>
 	 * UncertainDouble.of(3.27, 0.22).toString(false) = "3.3"
-	 * UncertainDouble.of(3.27, 0.22).toString(true) = "3.3 ± 0.2"
+	 * UncertainDouble.of(3.27, 0.22).toString(true) = "3.3 � 0.2"
 	 * UncertainDouble.of(3.27, 0.13).toString(false) = "3.27"
-	 * UncertainDouble.of(3.27, 0.13).toString(true) = "3.27 ± 0.13"
+	 * UncertainDouble.of(3.27, 0.13).toString(true) = "3.27 � 0.13"
 	 * UncertainDouble.of(-5.01, 0).toString(false) = "-5.01"
-	 * UncertainDouble.of(-5.01, 0).toString(true) = "-5.01 ± 0.0"
+	 * UncertainDouble.of(-5.01, 0).toString(true) = "-5.01 � 0.0"
 	 * </pre>
 	 * 
 	 * @since 2020-09-07
@@ -397,31 +397,31 @@ public final class UncertainDouble implements Comparable<UncertainDouble> {
 	public final String toString(boolean showUncertainty,
 			RoundingMode roundingMode) {
 		String valueString, uncertaintyString;
-		
+
 		// generate the string representation of value and uncertainty
 		if (this.isExact()) {
 			uncertaintyString = "0.0";
 			valueString = Double.toString(this.value);
-			
+
 		} else {
 			// round the value and uncertainty according to getDisplayScale()
 			final BigDecimal bigValue = BigDecimal.valueOf(this.value);
 			final BigDecimal bigUncertainty = BigDecimal.valueOf(this.uncertainty);
-			
+
 			final int displayScale = this.getDisplayScale();
 			final BigDecimal roundedUncertainty = bigUncertainty
 					.setScale(displayScale, roundingMode);
 			final BigDecimal roundedValue = bigValue.setScale(displayScale,
 					roundingMode);
-			
+
 			valueString = roundedValue.toString();
 			uncertaintyString = roundedUncertainty.toString();
 		}
-		
-		// return "value" or "value ± uncertainty" depending on showUncertainty
-		return valueString + (showUncertainty ? " ± " + uncertaintyString : "");
+
+		// return "value" or "value � uncertainty" depending on showUncertainty
+		return valueString + (showUncertainty ? " � " + uncertaintyString : "");
 	}
-	
+
 	/**
 	 * @return absolute uncertainty
 	 * @since 2020-09-07
@@ -429,7 +429,7 @@ public final class UncertainDouble implements Comparable<UncertainDouble> {
 	public final double uncertainty() {
 		return this.uncertainty;
 	}
-	
+
 	/**
 	 * @return value without uncertainty
 	 * @since 2020-09-07