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diff --git a/src/main/java/sevenUnitsGUI/StandardDisplayRules.java b/src/main/java/sevenUnitsGUI/StandardDisplayRules.java
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+/**
+ * Copyright (C) 2022 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
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * 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 sevenUnitsGUI;
+
+import java.math.BigDecimal;
+import java.math.MathContext;
+import java.math.RoundingMode;
+import java.util.function.Function;
+import java.util.regex.Pattern;
+
+import sevenUnits.utils.UncertainDouble;
+
+/**
+ * A static utility class that can be used to make display rules for the
+ * presenter.
+ *
+ * @since 2022-04-18
+ */
+public final class StandardDisplayRules {
+	/**
+	 * A rule that rounds to a fixed number of decimal places.
+	 *
+	 * @since 2022-04-18
+	 */
+	public static final class FixedDecimals
+			implements Function<UncertainDouble, String> {
+		public static final Pattern TO_STRING_PATTERN = Pattern
+				.compile("Round to (\\d+) decimal places");
+		/**
+		 * The number of places to round to.
+		 */
+		private final int decimalPlaces;
+		
+		/**
+		 * @param decimalPlaces
+		 * @since 2022-04-18
+		 */
+		private FixedDecimals(int decimalPlaces) {
+			this.decimalPlaces = decimalPlaces;
+		}
+		
+		@Override
+		public String apply(UncertainDouble t) {
+			final var toRound = new BigDecimal(t.value());
+			return toRound.setScale(this.decimalPlaces, RoundingMode.HALF_EVEN)
+					.toPlainString();
+		}
+		
+		/**
+		 * @return the number of decimal places this rule rounds to
+		 * @since 2022-04-18
+		 */
+		public int decimalPlaces() {
+			return this.decimalPlaces;
+		}
+		
+		@Override
+		public boolean equals(Object obj) {
+			if (this == obj)
+				return true;
+			if (!(obj instanceof FixedDecimals))
+				return false;
+			final FixedDecimals other = (FixedDecimals) obj;
+			if (this.decimalPlaces != other.decimalPlaces)
+				return false;
+			return true;
+		}
+		
+		@Override
+		public int hashCode() {
+			return 31 + this.decimalPlaces;
+		}
+		
+		@Override
+		public String toString() {
+			return "Round to " + this.decimalPlaces + " decimal places";
+		}
+	}
+	
+	/**
+	 * A rule that rounds to a fixed number of significant digits.
+	 *
+	 * @since 2022-04-18
+	 */
+	public static final class FixedPrecision
+			implements Function<UncertainDouble, String> {
+		public static final Pattern TO_STRING_PATTERN = Pattern
+				.compile("Round to (\\d+) significant figures");
+		
+		/**
+		 * The number of significant figures to round to.
+		 */
+		private final MathContext mathContext;
+		
+		/**
+		 * @param significantFigures
+		 * @since 2022-04-18
+		 */
+		private FixedPrecision(int significantFigures) {
+			this.mathContext = new MathContext(significantFigures,
+					RoundingMode.HALF_EVEN);
+		}
+		
+		@Override
+		public String apply(UncertainDouble t) {
+			final var toRound = new BigDecimal(t.value());
+			return toRound.round(this.mathContext).toString();
+		}
+		
+		@Override
+		public boolean equals(Object obj) {
+			if (this == obj)
+				return true;
+			if (!(obj instanceof FixedPrecision))
+				return false;
+			final FixedPrecision other = (FixedPrecision) obj;
+			if (this.mathContext == null) {
+				if (other.mathContext != null)
+					return false;
+			} else if (!this.mathContext.equals(other.mathContext))
+				return false;
+			return true;
+		}
+		
+		@Override
+		public int hashCode() {
+			return 127
+					+ (this.mathContext == null ? 0 : this.mathContext.hashCode());
+		}
+		
+		/**
+		 * @return the number of significant figures this rule rounds to
+		 * @since 2022-04-18
+		 */
+		public int significantFigures() {
+			return this.mathContext.getPrecision();
+		}
+		
+		@Override
+		public String toString() {
+			return "Round to " + this.mathContext.getPrecision()
+					+ " significant figures";
+		}
+	}
+	
+	/**
+	 * A rounding rule that rounds based on UncertainDouble's toString method.
+	 * This means the output will have around as many significant figures as the
+	 * input.
+	 *
+	 * @since 2022-04-18
+	 */
+	public static final class UncertaintyBased
+			implements Function<UncertainDouble, String> {
+		private UncertaintyBased() {}
+		
+		@Override
+		public String apply(UncertainDouble t) {
+			return t.toString(false, RoundingMode.HALF_EVEN);
+		}
+		
+		@Override
+		public String toString() {
+			return "Uncertainty-Based Rounding";
+		}
+	}
+	
+	/**
+	 * For now, I want this to be a singleton. I might want to add a parameter
+	 * later, so I won't make it an enum.
+	 */
+	private static final UncertaintyBased UNCERTAINTY_BASED_ROUNDING_RULE = new UncertaintyBased();
+	
+	/**
+	 * @param decimalPlaces decimal places to round to
+	 * @return a rounding rule that rounds to fixed number of decimal places
+	 * @since 2022-04-18
+	 */
+	public static final FixedDecimals fixedDecimals(int decimalPlaces) {
+		return new FixedDecimals(decimalPlaces);
+	}
+	
+	/**
+	 * @param significantFigures significant figures to round to
+	 * @return a rounding rule that rounds to a fixed number of significant
+	 *         figures
+	 * @since 2022-04-18
+	 */
+	public static final FixedPrecision fixedPrecision(int significantFigures) {
+		return new FixedPrecision(significantFigures);
+	}
+	
+	/**
+	 * Gets one of the standard rules from its string representation.
+	 *
+	 * @param ruleToString string representation of the display rule
+	 * @return display rule
+	 * @throws IllegalArgumentException if the provided string is not that of a
+	 *                                  standard rule.
+	 * @since 2021-12-24
+	 */
+	public static final Function<UncertainDouble, String> getStandardRule(
+			String ruleToString) {
+		if (UNCERTAINTY_BASED_ROUNDING_RULE.toString().equals(ruleToString))
+			return UNCERTAINTY_BASED_ROUNDING_RULE;
+		
+		// test if it is a fixed-places rule
+		final var placesMatch = FixedDecimals.TO_STRING_PATTERN
+				.matcher(ruleToString);
+		if (placesMatch.matches())
+			return new FixedDecimals(Integer.valueOf(placesMatch.group(1)));
+		
+		// test if it is a fixed-sig-fig rule
+		final var sigFigMatch = FixedPrecision.TO_STRING_PATTERN
+				.matcher(ruleToString);
+		if (sigFigMatch.matches())
+			return new FixedPrecision(Integer.valueOf(sigFigMatch.group(1)));
+		
+		throw new IllegalArgumentException(
+				"Provided string does not match any given rules.");
+	}
+	
+	/**
+	 * @return an UncertainDouble-based rounding rule
+	 * @since 2022-04-18
+	 */
+	public static final UncertaintyBased uncertaintyBased() {
+		return UNCERTAINTY_BASED_ROUNDING_RULE;
+	}
+	
+	private StandardDisplayRules() {}
+}