am 8f27d2a4: am e61089e5: Increase number of guard digits

* commit '8f27d2a402c9bd909d8f851e8ae323ba427f0f13':
  Increase number of guard digits

1 files changed, 9 insertions, 1 deletions

diff --git a/src/com/android/calculator2/CalculatorExpressionEvaluator.java b/src/com/android/calculator2/CalculatorExpressionEvaluator.java
index 26cd404..85d719b 100644
--- a/src/com/android/calculator2/CalculatorExpressionEvaluator.java
+++ b/src/com/android/calculator2/CalculatorExpressionEvaluator.java
@@ -22,8 +22,16 @@ import org.javia.arity.Util;
 
 public class CalculatorExpressionEvaluator {
 
+    /**
+     * The maximum number of significant digits to display.
+     */
     private static final int MAX_DIGITS = 12;
-    private static final int ROUNDING_DIGITS = 2;
+
+    /**
+     * A {@link Double} has at least 17 significant digits, we show the first {@link #MAX_DIGITS}
+     * and use the remaining digits as guard digits to hide floating point precision errors.
+     */
+    private static final int ROUNDING_DIGITS = Math.max(17 - MAX_DIGITS, 0);
 
     private final Symbols mSymbols;
     private final CalculatorExpressionTokenizer mTokenizer;