Merge branch 'new-documentation-0.3.1' into develop

27 files changed, 186 insertions, 189 deletions

diff --git a/src/main/java/sevenUnits/converterGUI/DefaultPrefixRepetitionRule.java b/src/main/java/sevenUnits/converterGUI/DefaultPrefixRepetitionRule.java
index 835651e..6b6abf0 100644
--- a/src/main/java/sevenUnits/converterGUI/DefaultPrefixRepetitionRule.java
+++ b/src/main/java/sevenUnits/converterGUI/DefaultPrefixRepetitionRule.java
@@ -6,7 +6,7 @@ package sevenUnits.converterGUI;
 import java.util.List;
 import java.util.function.Predicate;
 
-import sevenUnits.unit.SI;
+import sevenUnits.unit.Metric;
 import sevenUnits.unit.UnitPrefix;
 
 /**
@@ -49,7 +49,7 @@ enum DefaultPrefixRepetitionRule implements Predicate<List<UnitPrefix>> {
 			// if the first prefix is non-metric (including binary prefixes),
 			// assume we are using non-metric prefixes
 			// non-metric prefixes are allowed, but can't be repeated.
-			if (!SI.DECIMAL_PREFIXES.contains(prefixes.get(0)))
+			if (!Metric.DECIMAL_PREFIXES.contains(prefixes.get(0)))
 				return NO_REPETITION.test(prefixes);
 			
 			int part = 0; // 0=yotta/yoctos, 1=kilo-zetta/milli-zepto,
@@ -58,7 +58,7 @@ enum DefaultPrefixRepetitionRule implements Predicate<List<UnitPrefix>> {
 			for (final UnitPrefix prefix : prefixes) {
 				// check that the current prefix is metric and appropriately
 				// magnifying/reducing
-				if (!SI.DECIMAL_PREFIXES.contains(prefix))
+				if (!Metric.DECIMAL_PREFIXES.contains(prefix))
 					return false;
 				if (magnifying != prefix.getMultiplier() > 1)
 					return false;
@@ -72,7 +72,7 @@ enum DefaultPrefixRepetitionRule implements Predicate<List<UnitPrefix>> {
 					break;
 				case 1:
 					// after a kilo-zetta, only deka/hecto are valid
-					if (SI.THOUSAND_PREFIXES.contains(prefix))
+					if (Metric.THOUSAND_PREFIXES.contains(prefix))
 						return false;
 					break;
 				case 2:
@@ -81,9 +81,9 @@ enum DefaultPrefixRepetitionRule implements Predicate<List<UnitPrefix>> {
 				}
 				
 				// set part
-				if (SI.YOTTA.equals(prefix) || SI.YOCTO.equals(prefix)) {
+				if (Metric.YOTTA.equals(prefix) || Metric.YOCTO.equals(prefix)) {
 					part = 0;
-				} else if (SI.THOUSAND_PREFIXES.contains(prefix)) {
+				} else if (Metric.THOUSAND_PREFIXES.contains(prefix)) {
 					part = 1;
 				} else {
 					part = 2;
diff --git a/src/main/java/sevenUnits/converterGUI/SevenUnitsGUI.java b/src/main/java/sevenUnits/converterGUI/SevenUnitsGUI.java
index fb498da..bfd5974 100644
--- a/src/main/java/sevenUnits/converterGUI/SevenUnitsGUI.java
+++ b/src/main/java/sevenUnits/converterGUI/SevenUnitsGUI.java
@@ -65,18 +65,18 @@ import javax.swing.WindowConstants;
 import javax.swing.border.TitledBorder;
 
 import sevenUnits.ProgramInfo;
-import sevenUnits.math.ConditionalExistenceCollections;
-import sevenUnits.math.ObjectProduct;
 import sevenUnits.unit.BaseDimension;
 import sevenUnits.unit.BritishImperial;
 import sevenUnits.unit.LinearUnit;
 import sevenUnits.unit.LinearUnitValue;
 import sevenUnits.unit.NameSymbol;
-import sevenUnits.unit.SI;
+import sevenUnits.unit.Metric;
 import sevenUnits.unit.Unit;
 import sevenUnits.unit.UnitDatabase;
 import sevenUnits.unit.UnitPrefix;
 import sevenUnits.unit.UnitValue;
+import sevenUnits.utils.ConditionalExistenceCollections;
+import sevenUnits.utils.ObjectProduct;
 
 /**
  * @author Adrien Hopkins
@@ -110,25 +110,25 @@ final class SevenUnitsGUI {
 		 * @since v0.2.0
 		 */
 		private static void addDefaults(final UnitDatabase database) {
-			database.addUnit("metre", SI.METRE);
-			database.addUnit("kilogram", SI.KILOGRAM);
-			database.addUnit("gram", SI.KILOGRAM.dividedBy(1000));
-			database.addUnit("second", SI.SECOND);
-			database.addUnit("ampere", SI.AMPERE);
-			database.addUnit("kelvin", SI.KELVIN);
-			database.addUnit("mole", SI.MOLE);
-			database.addUnit("candela", SI.CANDELA);
-			database.addUnit("bit", SI.BIT);
-			database.addUnit("unit", SI.ONE);
+			database.addUnit("metre", Metric.METRE);
+			database.addUnit("kilogram", Metric.KILOGRAM);
+			database.addUnit("gram", Metric.KILOGRAM.dividedBy(1000));
+			database.addUnit("second", Metric.SECOND);
+			database.addUnit("ampere", Metric.AMPERE);
+			database.addUnit("kelvin", Metric.KELVIN);
+			database.addUnit("mole", Metric.MOLE);
+			database.addUnit("candela", Metric.CANDELA);
+			database.addUnit("bit", Metric.BIT);
+			database.addUnit("unit", Metric.ONE);
 			// nonlinear units - must be loaded manually
-			database.addUnit("tempCelsius", SI.CELSIUS);
+			database.addUnit("tempCelsius", Metric.CELSIUS);
 			database.addUnit("tempFahrenheit", BritishImperial.FAHRENHEIT);
 			
 			// load initial dimensions
-			database.addDimension("LENGTH", SI.Dimensions.LENGTH);
-			database.addDimension("MASS", SI.Dimensions.MASS);
-			database.addDimension("TIME", SI.Dimensions.TIME);
-			database.addDimension("TEMPERATURE", SI.Dimensions.TEMPERATURE);
+			database.addDimension("LENGTH", Metric.Dimensions.LENGTH);
+			database.addDimension("MASS", Metric.Dimensions.MASS);
+			database.addDimension("TIME", Metric.Dimensions.TIME);
+			database.addDimension("TEMPERATURE", Metric.Dimensions.TEMPERATURE);
 		}
 		
 		/**
diff --git a/src/main/java/sevenUnits/unit/BaseUnit.java b/src/main/java/sevenUnits/unit/BaseUnit.java
index b1e30fb..ee2c277 100644
--- a/src/main/java/sevenUnits/unit/BaseUnit.java
+++ b/src/main/java/sevenUnits/unit/BaseUnit.java
@@ -75,7 +75,7 @@ public final class BaseUnit extends Unit {
 	 */
 	private BaseUnit(final BaseDimension dimension, final String primaryName,
 			final String symbol, final Set<String> otherNames) {
-		super(primaryName, symbol, otherNames);
+		super(NameSymbol.of(primaryName, symbol, otherNames));
 		this.dimension = Objects.requireNonNull(dimension,
 				"dimension must not be null.");
 	}
diff --git a/src/main/java/sevenUnits/unit/BritishImperial.java b/src/main/java/sevenUnits/unit/BritishImperial.java
index 63da7f0..81a3f2a 100644
--- a/src/main/java/sevenUnits/unit/BritishImperial.java
+++ b/src/main/java/sevenUnits/unit/BritishImperial.java
@@ -48,7 +48,7 @@ public final class BritishImperial {
 		/**
 		 * According to the International Yard and Pound of 1959, a yard is defined as exactly 0.9144 metres.
 		 */
-		public static final LinearUnit YARD = SI.METRE.times(0.9144);
+		public static final LinearUnit YARD = Metric.METRE.times(0.9144);
 		public static final LinearUnit FOOT = YARD.dividedBy(3);
 		public static final LinearUnit INCH = FOOT.dividedBy(12);
 		public static final LinearUnit THOU = INCH.dividedBy(1000);
@@ -57,7 +57,7 @@ public final class BritishImperial {
 		public static final LinearUnit MILE = FURLONG.times(8);
 		public static final LinearUnit LEAGUE = MILE.times(3);
 
-		public static final LinearUnit NAUTICAL_MILE = SI.METRE.times(1852);
+		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);
 
@@ -72,7 +72,7 @@ public final class BritishImperial {
 	 * @since 2019-11-08
 	 */
 	public static final class Mass {
-		public static final LinearUnit POUND = SI.GRAM.times(453.59237);
+		public static final LinearUnit POUND = Metric.GRAM.times(453.59237);
 		public static final LinearUnit OUNCE = POUND.dividedBy(16);
 		public static final LinearUnit DRACHM = POUND.dividedBy(256);
 		public static final LinearUnit GRAIN = POUND.dividedBy(7000);
@@ -80,7 +80,7 @@ public final class BritishImperial {
 		public static final LinearUnit QUARTER = STONE.times(2);
 		public static final LinearUnit HUNDREDWEIGHT = QUARTER.times(4);
 		public static final LinearUnit LONG_TON = HUNDREDWEIGHT.times(20);
-		public static final LinearUnit SLUG = SI.KILOGRAM.times(14.59390294);
+		public static final LinearUnit SLUG = Metric.KILOGRAM.times(14.59390294);
 	}
 
 	/**
@@ -90,7 +90,7 @@ public final class BritishImperial {
 	 * @since 2019-11-08
 	 */
 	public static final class Volume {
-		public static final LinearUnit FLUID_OUNCE = SI.LITRE.withPrefix(SI.MILLI).times(28.4130625);
+		public static final LinearUnit FLUID_OUNCE = Metric.LITRE.withPrefix(Metric.MILLI).times(28.4130625);
 		public static final LinearUnit GILL = FLUID_OUNCE.times(5);
 		public static final LinearUnit PINT = FLUID_OUNCE.times(20);
 		public static final LinearUnit QUART = PINT.times(2);
@@ -104,13 +104,13 @@ public final class BritishImperial {
 		public static final LinearUnit ACRE_FOOT = Area.ACRE.times(Length.FOOT);
 	}
 
-	public static final LinearUnit OUNCE_FORCE = Mass.OUNCE.times(SI.Constants.EARTH_GRAVITY);
-	public static final LinearUnit POUND_FORCE = Mass.POUND.times(SI.Constants.EARTH_GRAVITY);
+	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 = SI.JOULE.times(1055.06);
-	public static final LinearUnit CALORIE = SI.JOULE.times(4.184);
-	public static final LinearUnit KILOCALORIE = SI.JOULE.times(4184);
+	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(SI.KELVIN.getBase(),
+	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 7bacc9d..df457e4 100644
--- a/src/main/java/sevenUnits/unit/FunctionalUnit.java
+++ b/src/main/java/sevenUnits/unit/FunctionalUnit.java
@@ -19,7 +19,7 @@ package sevenUnits.unit;
 import java.util.Objects;
 import java.util.function.DoubleUnaryOperator;
 
-import sevenUnits.math.ObjectProduct;
+import sevenUnits.utils.ObjectProduct;
 
 /**
  * A unit that uses functional objects to convert to and from its base.
diff --git a/src/main/java/sevenUnits/unit/FunctionalUnitlike.java b/src/main/java/sevenUnits/unit/FunctionalUnitlike.java
index 61503e8..2ee9e19 100644
--- a/src/main/java/sevenUnits/unit/FunctionalUnitlike.java
+++ b/src/main/java/sevenUnits/unit/FunctionalUnitlike.java
@@ -19,7 +19,7 @@ package sevenUnits.unit;
 import java.util.function.DoubleFunction;
 import java.util.function.ToDoubleFunction;
 
-import sevenUnits.math.ObjectProduct;
+import sevenUnits.utils.ObjectProduct;
 
 /**
  * A unitlike form that converts using two conversion functions.
diff --git a/src/main/java/sevenUnits/unit/LinearUnit.java b/src/main/java/sevenUnits/unit/LinearUnit.java
index 7c46443..25c2e2e 100644
--- a/src/main/java/sevenUnits/unit/LinearUnit.java
+++ b/src/main/java/sevenUnits/unit/LinearUnit.java
@@ -18,9 +18,9 @@ package sevenUnits.unit;
 
 import java.util.Objects;
 
-import sevenUnits.math.DecimalComparison;
-import sevenUnits.math.ObjectProduct;
-import sevenUnits.math.UncertainDouble;
+import sevenUnits.utils.DecimalComparison;
+import sevenUnits.utils.ObjectProduct;
+import sevenUnits.utils.UncertainDouble;
 
 /**
  * A unit that can be expressed as a product of its base and a number. For
diff --git a/src/main/java/sevenUnits/unit/LinearUnitValue.java b/src/main/java/sevenUnits/unit/LinearUnitValue.java
index 687a8b4..a36d568 100644
--- a/src/main/java/sevenUnits/unit/LinearUnitValue.java
+++ b/src/main/java/sevenUnits/unit/LinearUnitValue.java
@@ -19,8 +19,8 @@ package sevenUnits.unit;
 import java.util.Objects;
 import java.util.Optional;
 
-import sevenUnits.math.DecimalComparison;
-import sevenUnits.math.UncertainDouble;
+import sevenUnits.utils.DecimalComparison;
+import sevenUnits.utils.UncertainDouble;
 
 /**
  * A possibly uncertain value expressed in a linear unit.
@@ -32,7 +32,7 @@ import sevenUnits.math.UncertainDouble;
  * @since 2020-07-26
  */
 public final class LinearUnitValue {
-	public static final LinearUnitValue ONE = getExact(SI.ONE, 1);
+	public static final LinearUnitValue ONE = getExact(Metric.ONE, 1);
 	
 	/**
 	 * Gets an exact {@code LinearUnitValue}
diff --git a/src/main/java/sevenUnits/unit/SI.java b/src/main/java/sevenUnits/unit/Metric.java
index e0e5a54..3c4d291 100644
--- a/src/main/java/sevenUnits/unit/SI.java
+++ b/src/main/java/sevenUnits/unit/Metric.java
@@ -18,7 +18,7 @@ package sevenUnits.unit;
 
 import java.util.Set;
 
-import sevenUnits.math.ObjectProduct;
+import sevenUnits.utils.ObjectProduct;
 
 /**
  * All of the units, prefixes and dimensions that are used by the SI, as well as
@@ -36,7 +36,7 @@ import sevenUnits.math.ObjectProduct;
  * @author Adrien Hopkins
  * @since 2019-10-16
  */
-public final class SI {
+public final class Metric {
 	/// dimensions used by SI units
 	// base dimensions, as BaseDimensions
 	public static final class BaseDimensions {
@@ -402,57 +402,57 @@ public final class SI {
 			.withName(NameSymbol.of("exbi", "Ei"));
 	
 	// a few prefixed units
-	public static final LinearUnit MICROMETRE = SI.METRE.withPrefix(SI.MICRO);
-	public static final LinearUnit MILLIMETRE = SI.METRE.withPrefix(SI.MILLI);
-	public static final LinearUnit KILOMETRE = SI.METRE.withPrefix(SI.KILO);
-	public static final LinearUnit MEGAMETRE = SI.METRE.withPrefix(SI.MEGA);
+	public static final LinearUnit MICROMETRE = Metric.METRE.withPrefix(Metric.MICRO);
+	public static final LinearUnit MILLIMETRE = Metric.METRE.withPrefix(Metric.MILLI);
+	public static final LinearUnit KILOMETRE = Metric.METRE.withPrefix(Metric.KILO);
+	public static final LinearUnit MEGAMETRE = Metric.METRE.withPrefix(Metric.MEGA);
 	
-	public static final LinearUnit MICROLITRE = SI.LITRE.withPrefix(SI.MICRO);
-	public static final LinearUnit MILLILITRE = SI.LITRE.withPrefix(SI.MILLI);
-	public static final LinearUnit KILOLITRE = SI.LITRE.withPrefix(SI.KILO);
-	public static final LinearUnit MEGALITRE = SI.LITRE.withPrefix(SI.MEGA);
+	public static final LinearUnit MICROLITRE = Metric.LITRE.withPrefix(Metric.MICRO);
+	public static final LinearUnit MILLILITRE = Metric.LITRE.withPrefix(Metric.MILLI);
+	public static final LinearUnit KILOLITRE = Metric.LITRE.withPrefix(Metric.KILO);
+	public static final LinearUnit MEGALITRE = Metric.LITRE.withPrefix(Metric.MEGA);
 	
-	public static final LinearUnit MICROSECOND = SI.SECOND.withPrefix(SI.MICRO);
-	public static final LinearUnit MILLISECOND = SI.SECOND.withPrefix(SI.MILLI);
-	public static final LinearUnit KILOSECOND = SI.SECOND.withPrefix(SI.KILO);
-	public static final LinearUnit MEGASECOND = SI.SECOND.withPrefix(SI.MEGA);
+	public static final LinearUnit MICROSECOND = Metric.SECOND.withPrefix(Metric.MICRO);
+	public static final LinearUnit MILLISECOND = Metric.SECOND.withPrefix(Metric.MILLI);
+	public static final LinearUnit KILOSECOND = Metric.SECOND.withPrefix(Metric.KILO);
+	public static final LinearUnit MEGASECOND = Metric.SECOND.withPrefix(Metric.MEGA);
 	
-	public static final LinearUnit MICROGRAM = SI.GRAM.withPrefix(SI.MICRO);
-	public static final LinearUnit MILLIGRAM = SI.GRAM.withPrefix(SI.MILLI);
-	public static final LinearUnit MEGAGRAM = SI.GRAM.withPrefix(SI.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 = SI.NEWTON.withPrefix(SI.MICRO);
-	public static final LinearUnit MILLINEWTON = SI.NEWTON.withPrefix(SI.MILLI);
-	public static final LinearUnit KILONEWTON = SI.NEWTON.withPrefix(SI.KILO);
-	public static final LinearUnit MEGANEWTON = SI.NEWTON.withPrefix(SI.MEGA);
+	public static final LinearUnit MICRONEWTON = Metric.NEWTON.withPrefix(Metric.MICRO);
+	public static final LinearUnit MILLINEWTON = Metric.NEWTON.withPrefix(Metric.MILLI);
+	public static final LinearUnit KILONEWTON = Metric.NEWTON.withPrefix(Metric.KILO);
+	public static final LinearUnit MEGANEWTON = Metric.NEWTON.withPrefix(Metric.MEGA);
 	
-	public static final LinearUnit MICROJOULE = SI.JOULE.withPrefix(SI.MICRO);
-	public static final LinearUnit MILLIJOULE = SI.JOULE.withPrefix(SI.MILLI);
-	public static final LinearUnit KILOJOULE = SI.JOULE.withPrefix(SI.KILO);
-	public static final LinearUnit MEGAJOULE = SI.JOULE.withPrefix(SI.MEGA);
+	public static final LinearUnit MICROJOULE = Metric.JOULE.withPrefix(Metric.MICRO);
+	public static final LinearUnit MILLIJOULE = Metric.JOULE.withPrefix(Metric.MILLI);
+	public static final LinearUnit KILOJOULE = Metric.JOULE.withPrefix(Metric.KILO);
+	public static final LinearUnit MEGAJOULE = Metric.JOULE.withPrefix(Metric.MEGA);
 	
-	public static final LinearUnit MICROWATT = SI.WATT.withPrefix(SI.MICRO);
-	public static final LinearUnit MILLIWATT = SI.WATT.withPrefix(SI.MILLI);
-	public static final LinearUnit KILOWATT = SI.WATT.withPrefix(SI.KILO);
-	public static final LinearUnit MEGAWATT = SI.WATT.withPrefix(SI.MEGA);
+	public static final LinearUnit MICROWATT = Metric.WATT.withPrefix(Metric.MICRO);
+	public static final LinearUnit MILLIWATT = Metric.WATT.withPrefix(Metric.MILLI);
+	public static final LinearUnit KILOWATT = Metric.WATT.withPrefix(Metric.KILO);
+	public static final LinearUnit MEGAWATT = Metric.WATT.withPrefix(Metric.MEGA);
 	
-	public static final LinearUnit MICROCOULOMB = SI.COULOMB
-			.withPrefix(SI.MICRO);
-	public static final LinearUnit MILLICOULOMB = SI.COULOMB
-			.withPrefix(SI.MILLI);
-	public static final LinearUnit KILOCOULOMB = SI.COULOMB.withPrefix(SI.KILO);
-	public static final LinearUnit MEGACOULOMB = SI.COULOMB.withPrefix(SI.MEGA);
+	public static final LinearUnit MICROCOULOMB = Metric.COULOMB
+			.withPrefix(Metric.MICRO);
+	public static final LinearUnit MILLICOULOMB = Metric.COULOMB
+			.withPrefix(Metric.MILLI);
+	public static final LinearUnit KILOCOULOMB = Metric.COULOMB.withPrefix(Metric.KILO);
+	public static final LinearUnit MEGACOULOMB = Metric.COULOMB.withPrefix(Metric.MEGA);
 	
-	public static final LinearUnit MICROAMPERE = SI.AMPERE.withPrefix(SI.MICRO);
-	public static final LinearUnit MILLIAMPERE = SI.AMPERE.withPrefix(SI.MILLI);
+	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 = SI.VOLT.withPrefix(SI.MICRO);
-	public static final LinearUnit MILLIVOLT = SI.VOLT.withPrefix(SI.MILLI);
-	public static final LinearUnit KILOVOLT = SI.VOLT.withPrefix(SI.KILO);
-	public static final LinearUnit MEGAVOLT = SI.VOLT.withPrefix(SI.MEGA);
+	public static final LinearUnit MICROVOLT = Metric.VOLT.withPrefix(Metric.MICRO);
+	public static final LinearUnit MILLIVOLT = Metric.VOLT.withPrefix(Metric.MILLI);
+	public static final LinearUnit KILOVOLT = Metric.VOLT.withPrefix(Metric.KILO);
+	public static final LinearUnit MEGAVOLT = Metric.VOLT.withPrefix(Metric.MEGA);
 	
-	public static final LinearUnit KILOOHM = SI.OHM.withPrefix(SI.KILO);
-	public static final LinearUnit MEGAOHM = SI.OHM.withPrefix(SI.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,
@@ -473,7 +473,7 @@ public final class SI {
 			MILLI, MICRO, NANO, PICO, FEMTO, ATTO, ZEPTO, YOCTO);
 	
 	// You may NOT get SI instances!
-	private SI() {
+	private Metric() {
 		throw new AssertionError();
 	}
 }
diff --git a/src/main/java/sevenUnits/unit/MultiUnit.java b/src/main/java/sevenUnits/unit/MultiUnit.java
index 014e055..83cdb03 100644
--- a/src/main/java/sevenUnits/unit/MultiUnit.java
+++ b/src/main/java/sevenUnits/unit/MultiUnit.java
@@ -20,7 +20,7 @@ import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.List;
 
-import sevenUnits.math.ObjectProduct;
+import sevenUnits.utils.ObjectProduct;
 
 /**
  * A combination of units, like "5 foot + 7 inch". All but the last units should
diff --git a/src/main/java/sevenUnits/unit/USCustomary.java b/src/main/java/sevenUnits/unit/USCustomary.java
index 76356c0..459071f 100644
--- a/src/main/java/sevenUnits/unit/USCustomary.java
+++ b/src/main/java/sevenUnits/unit/USCustomary.java
@@ -52,7 +52,7 @@ 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 = SI.METRE.times(1200.0 / 3937.0);
+		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);
@@ -97,7 +97,7 @@ 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 = SI.LITRE.withPrefix(SI.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 +112,7 @@ 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 = SI.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);
@@ -128,7 +128,7 @@ 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(SI.MINUTE).times(33000);
+	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 1e875af..005b6f7 100644
--- a/src/main/java/sevenUnits/unit/Unit.java
+++ b/src/main/java/sevenUnits/unit/Unit.java
@@ -17,14 +17,12 @@
 package sevenUnits.unit;
 
 import java.util.HashMap;
-import java.util.HashSet;
 import java.util.Map;
 import java.util.Objects;
-import java.util.Set;
 import java.util.function.DoubleUnaryOperator;
 
-import sevenUnits.math.DecimalComparison;
-import sevenUnits.math.ObjectProduct;
+import sevenUnits.utils.DecimalComparison;
+import sevenUnits.utils.ObjectProduct;
 
 /**
  * A unit that is composed of base units.
@@ -110,6 +108,19 @@ public abstract class Unit implements Nameable {
 	private transient ObjectProduct<BaseDimension> dimension = null;
 	
 	/**
+	 * A constructor that constructs {@code BaseUnit} instances.
+	 * 
+	 * @since 2019-10-16
+	 */
+	Unit(final NameSymbol nameSymbol) {
+		if (this instanceof BaseUnit) {
+			this.unitBase = ObjectProduct.oneOf((BaseUnit) this);
+		} else
+			throw new AssertionError();
+		this.nameSymbol = nameSymbol;
+	}
+	
+	/**
 	 * Creates the {@code Unit}.
 	 * 
 	 * @param unitBase base of unit
@@ -117,28 +128,13 @@ public abstract class Unit implements Nameable {
 	 * @since 2019-10-16
 	 * @throws NullPointerException if unitBase or ns is null
 	 */
-	Unit(ObjectProduct<BaseUnit> unitBase, NameSymbol ns) {
+	protected Unit(ObjectProduct<BaseUnit> unitBase, NameSymbol ns) {
 		this.unitBase = Objects.requireNonNull(unitBase,
 				"unitBase may not be null");
 		this.nameSymbol = Objects.requireNonNull(ns, "ns may not be null");
 	}
 	
 	/**
-	 * A constructor that constructs {@code BaseUnit} instances.
-	 * 
-	 * @since 2019-10-16
-	 */
-	Unit(final String primaryName, final String symbol,
-			final Set<String> otherNames) {
-		if (this instanceof BaseUnit) {
-			this.unitBase = ObjectProduct.oneOf((BaseUnit) this);
-		} else
-			throw new AssertionError();
-		this.nameSymbol = NameSymbol.of(primaryName, symbol,
-				new HashSet<>(otherNames));
-	}
-	
-	/**
 	 * @return this unit as a {@link Unitlike}
 	 * @since 2020-09-07
 	 */
@@ -342,7 +338,7 @@ public abstract class Unit implements Nameable {
 		
 		// second condition - check that
 		for (final BaseUnit b : linear.getBase().getBaseSet()) {
-			if (!SI.BaseUnits.BASE_UNITS.contains(b))
+			if (!Metric.BaseUnits.BASE_UNITS.contains(b))
 				return false;
 		}
 		
diff --git a/src/main/java/sevenUnits/unit/UnitDatabase.java b/src/main/java/sevenUnits/unit/UnitDatabase.java
index 1960229..b45d9cf 100644
--- a/src/main/java/sevenUnits/unit/UnitDatabase.java
+++ b/src/main/java/sevenUnits/unit/UnitDatabase.java
@@ -44,11 +44,11 @@ import java.util.function.Predicate;
 import java.util.regex.Matcher;
 import java.util.regex.Pattern;
 
-import sevenUnits.math.ConditionalExistenceCollections;
-import sevenUnits.math.DecimalComparison;
-import sevenUnits.math.ExpressionParser;
-import sevenUnits.math.ObjectProduct;
-import sevenUnits.math.UncertainDouble;
+import sevenUnits.utils.ConditionalExistenceCollections;
+import sevenUnits.utils.DecimalComparison;
+import sevenUnits.utils.ExpressionParser;
+import sevenUnits.utils.ObjectProduct;
+import sevenUnits.utils.UncertainDouble;
 
 /**
  * A database of units, prefixes and dimensions, and their names.
@@ -1116,7 +1116,7 @@ public final class UnitDatabase {
 	private static final LinearUnit exponentiateUnits(final LinearUnit base,
 			final LinearUnit exponentUnit) {
 		// exponent function - first check if o2 is a number,
-		if (exponentUnit.getBase().equals(SI.ONE.getBase())) {
+		if (exponentUnit.getBase().equals(Metric.ONE.getBase())) {
 			// then check if it is an integer,
 			final double exponent = exponentUnit.getConversionFactor();
 			if (DecimalComparison.equals(exponent % 1, 0))
@@ -1142,7 +1142,7 @@ public final class UnitDatabase {
 	private static final LinearUnitValue exponentiateUnitValues(
 			final LinearUnitValue base, final LinearUnitValue exponentValue) {
 		// exponent function - first check if o2 is a number,
-		if (exponentValue.canConvertTo(SI.ONE)) {
+		if (exponentValue.canConvertTo(Metric.ONE)) {
 			// then check if it is an integer,
 			final double exponent = exponentValue.getValueExact();
 			if (DecimalComparison.equals(exponent % 1, 0))
@@ -1676,7 +1676,7 @@ public final class UnitDatabase {
 			final BigDecimal number = new BigDecimal(name);
 			
 			final double uncertainty = Math.pow(10, -number.scale());
-			return LinearUnitValue.of(SI.ONE,
+			return LinearUnitValue.of(Metric.ONE,
 					UncertainDouble.of(number.doubleValue(), uncertainty));
 		} catch (final NumberFormatException e) {
 			return LinearUnitValue.getExact(this.getLinearUnit(name), 1);
@@ -1786,7 +1786,7 @@ public final class UnitDatabase {
 	public Unit getUnit(final String name) {
 		try {
 			final double value = Double.parseDouble(name);
-			return SI.ONE.times(value);
+			return Metric.ONE.times(value);
 		} catch (final NumberFormatException e) {
 			final Unit unit = this.units.get(name);
 			if (unit == null)
diff --git a/src/main/java/sevenUnits/unit/UnitPrefix.java b/src/main/java/sevenUnits/unit/UnitPrefix.java
index e4a27bd..308f4b0 100644
--- a/src/main/java/sevenUnits/unit/UnitPrefix.java
+++ b/src/main/java/sevenUnits/unit/UnitPrefix.java
@@ -20,7 +20,7 @@ import java.util.Objects;
 import java.util.Optional;
 import java.util.Set;
 
-import sevenUnits.math.DecimalComparison;
+import sevenUnits.utils.DecimalComparison;
 
 /**
  * A prefix that can be applied to a {@code LinearUnit} to multiply it by some value
diff --git a/src/main/java/sevenUnits/unit/Unitlike.java b/src/main/java/sevenUnits/unit/Unitlike.java
index fd361b6..d2dcbbb 100644
--- a/src/main/java/sevenUnits/unit/Unitlike.java
+++ b/src/main/java/sevenUnits/unit/Unitlike.java
@@ -22,7 +22,7 @@ import java.util.Objects;
 import java.util.function.DoubleFunction;
 import java.util.function.ToDoubleFunction;
 
-import sevenUnits.math.ObjectProduct;
+import sevenUnits.utils.ObjectProduct;
 
 /**
  * An object that can convert a value between multiple forms (instances of the
diff --git a/src/main/java/sevenUnits/math/ConditionalExistenceCollections.java b/src/main/java/sevenUnits/utils/ConditionalExistenceCollections.java
index 5ce1bd7..2adb579 100644
--- a/src/main/java/sevenUnits/math/ConditionalExistenceCollections.java
+++ b/src/main/java/sevenUnits/utils/ConditionalExistenceCollections.java
@@ -14,7 +14,7 @@
  * You should have received a copy of the GNU Affero General Public License
  * along with this program.  If not, see <https://www.gnu.org/licenses/>.
  */
-package sevenUnits.math;
+package sevenUnits.utils;
 
 import java.util.AbstractCollection;
 import java.util.AbstractMap;
diff --git a/src/main/java/sevenUnits/math/DecimalComparison.java b/src/main/java/sevenUnits/utils/DecimalComparison.java
index 24a9b2f..a5cbbaa 100644
--- a/src/main/java/sevenUnits/math/DecimalComparison.java
+++ b/src/main/java/sevenUnits/utils/DecimalComparison.java
@@ -14,7 +14,7 @@
  * You should have received a copy of the GNU Affero General Public License
  * along with this program.  If not, see <https://www.gnu.org/licenses/>.
  */
-package sevenUnits.math;
+package sevenUnits.utils;
 
 import java.math.BigDecimal;
 
diff --git a/src/main/java/sevenUnits/math/ExpressionParser.java b/src/main/java/sevenUnits/utils/ExpressionParser.java
index 5c8183b..1d3d44d 100644
--- a/src/main/java/sevenUnits/math/ExpressionParser.java
+++ b/src/main/java/sevenUnits/utils/ExpressionParser.java
@@ -14,7 +14,7 @@
  * You should have received a copy of the GNU Affero General Public License
  * along with this program.  If not, see <https://www.gnu.org/licenses/>.
  */
-package sevenUnits.math;
+package sevenUnits.utils;
 
 import java.util.ArrayDeque;
 import java.util.ArrayList;
diff --git a/src/main/java/sevenUnits/math/ObjectProduct.java b/src/main/java/sevenUnits/utils/ObjectProduct.java
index db95fd4..1dacb7d 100644
--- a/src/main/java/sevenUnits/math/ObjectProduct.java
+++ b/src/main/java/sevenUnits/utils/ObjectProduct.java
@@ -14,7 +14,7 @@
  * You should have received a copy of the GNU Affero General Public License
  * along with this program.  If not, see <https://www.gnu.org/licenses/>.
  */
-package sevenUnits.math;
+package sevenUnits.utils;
 
 import java.util.ArrayList;
 import java.util.Collections;
diff --git a/src/main/java/sevenUnits/math/UncertainDouble.java b/src/main/java/sevenUnits/utils/UncertainDouble.java
index b81bb79..8fe4b31 100644
--- a/src/main/java/sevenUnits/math/UncertainDouble.java
+++ b/src/main/java/sevenUnits/utils/UncertainDouble.java
@@ -14,7 +14,7 @@
  * You should have received a copy of the GNU Affero General Public License
  * along with this program.  If not, see <https://www.gnu.org/licenses/>.
  */
-package sevenUnits.math;
+package sevenUnits.utils;
 
 import java.math.BigDecimal;
 import java.math.RoundingMode;
diff --git a/src/main/java/sevenUnits/math/package-info.java b/src/main/java/sevenUnits/utils/package-info.java
index 62f72cd..350c62d 100644
--- a/src/main/java/sevenUnits/math/package-info.java
+++ b/src/main/java/sevenUnits/utils/package-info.java
@@ -1,5 +1,5 @@
 /**
- * Copyright (C) 2019 Adrien Hopkins
+ * Copyright (C) 2018-2020 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
@@ -15,10 +15,11 @@
  * along with this program.  If not, see <https://www.gnu.org/licenses/>.
  */
 /**
- * Supplementary classes that are not related to units, but are necessary for their function.
+ * Supplementary classes that are not related to units, but are necessary for
+ * their function.
  * 
  * @author Adrien Hopkins
  * @since 2019-03-14
  * @since v0.2.0
  */
-package sevenUnits.math;
\ No newline at end of file
+package sevenUnits.utils;
\ No newline at end of file
diff --git a/src/test/java/sevenUnits/unit/MultiUnitTest.java b/src/test/java/sevenUnits/unit/MultiUnitTest.java
index 82722af..d632118 100644
--- a/src/test/java/sevenUnits/unit/MultiUnitTest.java
+++ b/src/test/java/sevenUnits/unit/MultiUnitTest.java
@@ -27,7 +27,7 @@ import org.junit.jupiter.api.Test;
 
 import sevenUnits.unit.BritishImperial;
 import sevenUnits.unit.MultiUnit;
-import sevenUnits.unit.SI;
+import sevenUnits.unit.Metric;
 
 /**
  * Tests related to the {@code MultiUnit}.
@@ -42,7 +42,7 @@ class MultiUnitTest {
 		final MultiUnit footInch = MultiUnit.of(BritishImperial.Length.FOOT,
 				BritishImperial.Length.INCH);
 		
-		assertEquals(1702.0, footInch.convertTo(SI.METRE.withPrefix(SI.MILLI),
+		assertEquals(1702.0, footInch.convertTo(Metric.METRE.withPrefix(Metric.MILLI),
 				Arrays.asList(5.0, 7.0)), 1.0);
 		
 		for (int i = 0; i < 1000; i++) {
@@ -50,7 +50,7 @@ class MultiUnitTest {
 			final double inches = rng.nextDouble() * 12;
 			final double millimetres = feet * 304.8 + inches * 25.4;
 			
-			final List<Double> feetAndInches = SI.METRE.withPrefix(SI.MILLI)
+			final List<Double> feetAndInches = Metric.METRE.withPrefix(Metric.MILLI)
 					.convertTo(footInch, millimetres);
 			assertEquals(feet, feetAndInches.get(0), 1e-10);
 			assertEquals(inches, feetAndInches.get(1), 1e-10);
diff --git a/src/test/java/sevenUnits/unit/UnitDatabaseTest.java b/src/test/java/sevenUnits/unit/UnitDatabaseTest.java
index c706b5c..1d5e503 100644
--- a/src/test/java/sevenUnits/unit/UnitDatabaseTest.java
+++ b/src/test/java/sevenUnits/unit/UnitDatabaseTest.java
@@ -33,7 +33,7 @@ import org.junit.jupiter.api.Test;
 
 import sevenUnits.unit.LinearUnit;
 import sevenUnits.unit.NameSymbol;
-import sevenUnits.unit.SI;
+import sevenUnits.unit.Metric;
 import sevenUnits.unit.Unit;
 import sevenUnits.unit.UnitDatabase;
 import sevenUnits.unit.UnitPrefix;
@@ -48,18 +48,18 @@ import sevenUnits.unit.UnitPrefix;
  */
 class UnitDatabaseTest {
 	// some linear units and one nonlinear
-	private static final Unit U = SI.METRE;
-	private static final Unit V = SI.KILOGRAM;
-	private static final Unit W = SI.SECOND;
+	private static final Unit U = Metric.METRE;
+	private static final Unit V = Metric.KILOGRAM;
+	private static final Unit W = Metric.SECOND;
 	
 	// used for testing expressions
 	// J = U^2 * V / W^2
-	private static final LinearUnit J = SI.KILOGRAM.times(SI.METRE.toExponent(2))
-			.dividedBy(SI.SECOND.toExponent(2));
-	private static final LinearUnit K = SI.KELVIN;
+	private static final LinearUnit J = Metric.KILOGRAM.times(Metric.METRE.toExponent(2))
+			.dividedBy(Metric.SECOND.toExponent(2));
+	private static final LinearUnit K = Metric.KELVIN;
 	
 	private static final Unit NONLINEAR = Unit
-			.fromConversionFunctions(SI.METRE.getBase(), o -> o + 1, o -> o - 1);
+			.fromConversionFunctions(Metric.METRE.getBase(), o -> o + 1, o -> o - 1);
 	
 	// make the prefix values prime so I can tell which multiplications were made
 	private static final UnitPrefix A = UnitPrefix.valueOf(2)
diff --git a/src/test/java/sevenUnits/unit/UnitTest.java b/src/test/java/sevenUnits/unit/UnitTest.java
index d216ae8..a980054 100644
--- a/src/test/java/sevenUnits/unit/UnitTest.java
+++ b/src/test/java/sevenUnits/unit/UnitTest.java
@@ -26,13 +26,13 @@ import java.util.concurrent.ThreadLocalRandom;
 
 import org.junit.jupiter.api.Test;
 
-import sevenUnits.math.DecimalComparison;
 import sevenUnits.unit.LinearUnit;
 import sevenUnits.unit.LinearUnitValue;
 import sevenUnits.unit.NameSymbol;
-import sevenUnits.unit.SI;
+import sevenUnits.unit.Metric;
 import sevenUnits.unit.Unit;
 import sevenUnits.unit.UnitValue;
+import sevenUnits.utils.DecimalComparison;
 
 /**
  * Testing the various Unit classes. This is NOT part of this program's public
@@ -48,19 +48,19 @@ class UnitTest {
 	
 	@Test
 	public void testAdditionAndSubtraction() {
-		final LinearUnit inch = SI.METRE.times(0.0254)
+		final LinearUnit inch = Metric.METRE.times(0.0254)
 				.withName(NameSymbol.of("inch", "in"));
-		final LinearUnit foot = SI.METRE.times(0.3048)
+		final LinearUnit foot = Metric.METRE.times(0.3048)
 				.withName(NameSymbol.of("foot", "ft"));
 		
-		assertEquals(inch.plus(foot), SI.METRE.times(0.3302));
-		assertEquals(foot.minus(inch), SI.METRE.times(0.2794));
+		assertEquals(inch.plus(foot), Metric.METRE.times(0.3302));
+		assertEquals(foot.minus(inch), Metric.METRE.times(0.2794));
 		
 		// test with LinearUnitValue
-		final LinearUnitValue value1 = LinearUnitValue.getExact(SI.METRE, 15);
+		final LinearUnitValue value1 = LinearUnitValue.getExact(Metric.METRE, 15);
 		final LinearUnitValue value2 = LinearUnitValue.getExact(foot, 120);
-		final LinearUnitValue value3 = LinearUnitValue.getExact(SI.METRE, 0.5);
-		final LinearUnitValue value4 = LinearUnitValue.getExact(SI.KILOGRAM, 60);
+		final LinearUnitValue value3 = LinearUnitValue.getExact(Metric.METRE, 0.5);
+		final LinearUnitValue value4 = LinearUnitValue.getExact(Metric.KILOGRAM, 60);
 		
 		// make sure addition is done correctly
 		assertEquals(51.576, value1.plus(value2).getValueExact(), 0.001);
@@ -70,8 +70,8 @@ class UnitTest {
 		
 		// make sure addition uses the correct unit, and is still associative
 		// (ignoring floating-point rounding errors)
-		assertEquals(SI.METRE, value1.plus(value2).getUnit());
-		assertEquals(SI.METRE, value1.plus(value2).plus(value3).getUnit());
+		assertEquals(Metric.METRE, value1.plus(value2).getUnit());
+		assertEquals(Metric.METRE, value1.plus(value2).plus(value3).getUnit());
 		assertEquals(foot, value2.plus(value1).getUnit());
 		assertTrue(value1.plus(value2).equals(value2.plus(value1), true));
 		
@@ -81,7 +81,7 @@ class UnitTest {
 	
 	@Test
 	public void testConversion() {
-		final LinearUnit metre = SI.METRE;
+		final LinearUnit metre = Metric.METRE;
 		final Unit inch = metre.times(0.0254);
 		
 		final UnitValue value = UnitValue.of(inch, 75);
@@ -97,7 +97,7 @@ class UnitTest {
 			final double expected = testValue * conversionFactor;
 			
 			// test
-			final Unit unit = SI.METRE.times(conversionFactor);
+			final Unit unit = Metric.METRE.times(conversionFactor);
 			final double actual = unit.convertToBase(testValue);
 			
 			assertEquals(actual, expected,
@@ -107,17 +107,17 @@ class UnitTest {
 	
 	@Test
 	public void testEquals() {
-		final LinearUnit metre = SI.METRE;
-		final Unit meter = SI.BaseUnits.METRE.asLinearUnit();
+		final LinearUnit metre = Metric.METRE;
+		final Unit meter = Metric.BaseUnits.METRE.asLinearUnit();
 		
 		assertEquals(metre, meter);
 	}
 	
 	@Test
 	public void testIsMetric() {
-		final Unit metre = SI.METRE;
-		final Unit megasecond = SI.SECOND.withPrefix(SI.MEGA);
-		final Unit hour = SI.HOUR;
+		final Unit metre = Metric.METRE;
+		final Unit megasecond = Metric.SECOND.withPrefix(Metric.MEGA);
+		final Unit hour = Metric.HOUR;
 		
 		assertTrue(metre.isMetric());
 		assertTrue(megasecond.isMetric());
@@ -127,26 +127,26 @@ class UnitTest {
 	@Test
 	public void testMultiplicationAndDivision() {
 		// test unit-times-unit multiplication
-		final LinearUnit generatedJoule = SI.KILOGRAM
-				.times(SI.METRE.toExponent(2)).dividedBy(SI.SECOND.toExponent(2));
-		final LinearUnit actualJoule = SI.JOULE;
+		final LinearUnit generatedJoule = Metric.KILOGRAM
+				.times(Metric.METRE.toExponent(2)).dividedBy(Metric.SECOND.toExponent(2));
+		final LinearUnit actualJoule = Metric.JOULE;
 		
 		assertEquals(generatedJoule, actualJoule);
 		
 		// test multiplication by conversion factors
-		final LinearUnit kilometre = SI.METRE.times(1000);
-		final LinearUnit hour = SI.SECOND.times(3600);
+		final LinearUnit kilometre = Metric.METRE.times(1000);
+		final LinearUnit hour = Metric.SECOND.times(3600);
 		final LinearUnit generatedKPH = kilometre.dividedBy(hour);
 		
-		final LinearUnit actualKPH = SI.METRE.dividedBy(SI.SECOND).dividedBy(3.6);
+		final LinearUnit actualKPH = Metric.METRE.dividedBy(Metric.SECOND).dividedBy(3.6);
 		
 		assertEquals(generatedKPH, actualKPH);
 	}
 	
 	@Test
 	public void testPrefixes() {
-		final LinearUnit generatedKilometre = SI.METRE.withPrefix(SI.KILO);
-		final LinearUnit actualKilometre = SI.METRE.times(1000);
+		final LinearUnit generatedKilometre = Metric.METRE.withPrefix(Metric.KILO);
+		final LinearUnit actualKilometre = Metric.METRE.times(1000);
 		
 		assertEquals(generatedKilometre, actualKilometre);
 	}
diff --git a/src/test/java/sevenUnits/math/ConditionalExistenceCollectionsTest.java b/src/test/java/sevenUnits/utils/ConditionalExistenceCollectionsTest.java
index a35dc5a..46afe77 100644
--- a/src/test/java/sevenUnits/math/ConditionalExistenceCollectionsTest.java
+++ b/src/test/java/sevenUnits/utils/ConditionalExistenceCollectionsTest.java
@@ -14,7 +14,7 @@
  * You should have received a copy of the GNU Affero General Public License
  * along with this program.  If not, see <https://www.gnu.org/licenses/>.
  */
-package sevenUnits.math;
+package sevenUnits.utils;
 
 import static org.junit.jupiter.api.Assertions.assertEquals;
 import static org.junit.jupiter.api.Assertions.assertFalse;
@@ -31,8 +31,8 @@ import java.util.NoSuchElementException;
 
 import org.junit.jupiter.api.Test;
 
-import sevenUnits.math.ConditionalExistenceCollections;
-import sevenUnits.math.ConditionalExistenceCollections.ConditionalExistenceIterator;
+import sevenUnits.utils.ConditionalExistenceCollections;
+import sevenUnits.utils.ConditionalExistenceCollections.ConditionalExistenceIterator;
 
 /**
  * Tests the {@link #ConditionalExistenceCollections}.
diff --git a/src/test/java/sevenUnits/math/ExpressionParserTest.java b/src/test/java/sevenUnits/utils/ExpressionParserTest.java
index 4801233..29648ee 100644
--- a/src/test/java/sevenUnits/math/ExpressionParserTest.java
+++ b/src/test/java/sevenUnits/utils/ExpressionParserTest.java
@@ -14,13 +14,13 @@
  * You should have received a copy of the GNU Affero General Public License
  * along with this program.  If not, see <https://www.gnu.org/licenses/>.
  */
-package sevenUnits.math;
+package sevenUnits.utils;
 
 import static org.junit.jupiter.api.Assertions.assertEquals;
 
 import org.junit.jupiter.api.Test;
 
-import sevenUnits.math.ExpressionParser;
+import sevenUnits.utils.ExpressionParser;
 
 /**
  * A test for the {@code ExpressionParser} class. This is NOT part of this program's public API.
@@ -36,7 +36,7 @@ class ExpressionParserTest {
 			.addBinaryOperator("^", (o1, o2) -> (int) Math.pow(o1, o2), 2).build();
 
 	/**
-	 * Test method for {@link sevenUnits.math.ExpressionParser#parseExpression(java.lang.String)}.
+	 * Test method for {@link sevenUnits.utils.ExpressionParser#parseExpression(java.lang.String)}.
 	 */
 	@Test
 	public void testParseExpression() {
diff --git a/src/test/java/sevenUnits/math/ObjectProductTest.java b/src/test/java/sevenUnits/utils/ObjectProductTest.java
index 1734f26..13fd7ec 100644
--- a/src/test/java/sevenUnits/math/ObjectProductTest.java
+++ b/src/test/java/sevenUnits/utils/ObjectProductTest.java
@@ -14,23 +14,23 @@
  * You should have received a copy of the GNU Affero General Public License
  * along with this program.  If not, see <https://www.gnu.org/licenses/>.
  */
-package sevenUnits.math;
+package sevenUnits.utils;
 
 import static org.junit.jupiter.api.Assertions.assertEquals;
 import static org.junit.jupiter.api.Assertions.assertFalse;
-import static sevenUnits.unit.SI.Dimensions.AREA;
-import static sevenUnits.unit.SI.Dimensions.ENERGY;
-import static sevenUnits.unit.SI.Dimensions.LENGTH;
-import static sevenUnits.unit.SI.Dimensions.MASS;
-import static sevenUnits.unit.SI.Dimensions.MASS_DENSITY;
-import static sevenUnits.unit.SI.Dimensions.QUANTITY;
-import static sevenUnits.unit.SI.Dimensions.TIME;
-import static sevenUnits.unit.SI.Dimensions.VOLUME;
+import static sevenUnits.unit.Metric.Dimensions.AREA;
+import static sevenUnits.unit.Metric.Dimensions.ENERGY;
+import static sevenUnits.unit.Metric.Dimensions.LENGTH;
+import static sevenUnits.unit.Metric.Dimensions.MASS;
+import static sevenUnits.unit.Metric.Dimensions.MASS_DENSITY;
+import static sevenUnits.unit.Metric.Dimensions.QUANTITY;
+import static sevenUnits.unit.Metric.Dimensions.TIME;
+import static sevenUnits.unit.Metric.Dimensions.VOLUME;
 
 import org.junit.jupiter.api.Test;
 
-import sevenUnits.math.ObjectProduct;
-import sevenUnits.unit.SI;
+import sevenUnits.unit.Metric;
+import sevenUnits.utils.ObjectProduct;
 
 /**
  * Tests for {@link ObjectProduct} using BaseDimension as a test object. This is NOT part of this program's public API.
@@ -60,8 +60,8 @@ class ObjectProductTest {
 	 */
 	@Test
 	public void testExponents() {
-		assertEquals(1, LENGTH.getExponent(SI.BaseDimensions.LENGTH));
-		assertEquals(3, VOLUME.getExponent(SI.BaseDimensions.LENGTH));
+		assertEquals(1, LENGTH.getExponent(Metric.BaseDimensions.LENGTH));
+		assertEquals(3, VOLUME.getExponent(Metric.BaseDimensions.LENGTH));
 	}
 
 	/**