1 files changed, 20 insertions, 4 deletions

diff --git a/src/main/java/sevenUnits/utils/UncertainDouble.java b/src/main/java/sevenUnits/utils/UncertainDouble.java
index fe41104..ac523b3 100644
--- a/src/main/java/sevenUnits/utils/UncertainDouble.java
+++ b/src/main/java/sevenUnits/utils/UncertainDouble.java
@@ -46,6 +46,21 @@ public final class UncertainDouble implements Comparable<UncertainDouble> {
 			+ "(?:\\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.
+	 * 
+	 * @throws NumberFormatException if the argument is not a number
+	 *
+	 * @since 2022-04-18
+	 */
+	public static final UncertainDouble fromRoundedString(String s) {
+		final BigDecimal value = new BigDecimal(s);
+		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>
@@ -348,7 +363,7 @@ public final class UncertainDouble implements Comparable<UncertainDouble> {
 	 */
 	@Override
 	public final String toString() {
-		return this.toString(!this.isExact());
+		return this.toString(!this.isExact(), RoundingMode.HALF_EVEN);
 	}
 	
 	/**
@@ -379,7 +394,8 @@ public final class UncertainDouble implements Comparable<UncertainDouble> {
 	 * 
 	 * @since 2020-09-07
 	 */
-	public final String toString(boolean showUncertainty) {
+	public final String toString(boolean showUncertainty,
+			RoundingMode roundingMode) {
 		String valueString, uncertaintyString;
 		
 		// generate the string representation of value and uncertainty
@@ -394,9 +410,9 @@ public final class UncertainDouble implements Comparable<UncertainDouble> {
 			
 			final int displayScale = this.getDisplayScale();
 			final BigDecimal roundedUncertainty = bigUncertainty
-					.setScale(displayScale, RoundingMode.HALF_EVEN);
+					.setScale(displayScale, roundingMode);
 			final BigDecimal roundedValue = bigValue.setScale(displayScale,
-					RoundingMode.HALF_EVEN);
+					roundingMode);
 			
 			valueString = roundedValue.toString();
 			uncertaintyString = roundedUncertainty.toString();