svn commit: r746582 - in /commons/proper/math/trunk/src: java/org/apache/commons/math/util/MathUtils.java test/org/apache/commons/math/util/MathUtilsTest.java

[luc]

Author: luc
Date: Sat Feb 21 20:16:36 2009
New Revision: 746582

URL: http://svn.apache.org/viewvc?rev=746582&view=rev
Log:
handle NaN and infinities correctly in the MathUtils.equals method with 
tolerance

Modified:
    
commons/proper/math/trunk/src/java/org/apache/commons/math/util/MathUtils.java
    
commons/proper/math/trunk/src/test/org/apache/commons/math/util/MathUtilsTest.java

Modified: 
commons/proper/math/trunk/src/java/org/apache/commons/math/util/MathUtils.java
URL: 
http://svn.apache.org/viewvc/commons/proper/math/trunk/src/java/org/apache/commons/math/util/MathUtils.java?rev=746582&r1=746581&r2=746582&view=diff
==============================================================================
--- 
commons/proper/math/trunk/src/java/org/apache/commons/math/util/MathUtils.java 
(original)
+++ 
commons/proper/math/trunk/src/java/org/apache/commons/math/util/MathUtils.java 
Sat Feb 21 20:16:36 2009
@@ -373,6 +373,9 @@
     /**
      * Returns true iff both arguments are equal or within the range of allowed
      * error (inclusive).
+     * <p>
+     * Two NaNs are considered equals, as are two infinities with same size.
+     * </p>
      * 
      * @param x first value
      * @param y second value
@@ -380,7 +383,7 @@
      * @return true if the values are equal or within range of each other
      */
     public static boolean equals(double x, double y, double eps) {
-      return x == y || (x < y && (x + eps) >= y) || (x > y && x <= (y + eps));
+      return equals(x, y) || (Math.abs(y - x) <= eps);
     }
     
     /**

Modified: 
commons/proper/math/trunk/src/test/org/apache/commons/math/util/MathUtilsTest.java
URL: 
http://svn.apache.org/viewvc/commons/proper/math/trunk/src/test/org/apache/commons/math/util/MathUtilsTest.java?rev=746582&r1=746581&r2=746582&view=diff
==============================================================================
--- 
commons/proper/math/trunk/src/test/org/apache/commons/math/util/MathUtilsTest.java
 (original)
+++ 
commons/proper/math/trunk/src/test/org/apache/commons/math/util/MathUtilsTest.java
 Sat Feb 21 20:16:36 2009
@@ -336,11 +336,15 @@
     }
 
     public void testEqualsWithAllowedDelta() {
-        assertTrue(MathUtils.equals(153.0000, 153.0000, .0001));
-        assertTrue(MathUtils.equals(153.0000, 153.0001, .0001));
-        assertTrue(MathUtils.equals(152.9999, 153.0000, .0001));
-        assertFalse(MathUtils.equals(153.0000, 153.0001, .00001));
-        assertFalse(MathUtils.equals(152.9998, 153.0000, .0001));
+        assertTrue(MathUtils.equals(153.0000, 153.0000, .0625));
+        assertTrue(MathUtils.equals(153.0000, 153.0625, .0625));
+        assertTrue(MathUtils.equals(152.9375, 153.0000, .0625));
+        assertTrue(MathUtils.equals(Double.NaN, Double.NaN, 1.0));
+        assertTrue(MathUtils.equals(Double.POSITIVE_INFINITY, 
Double.POSITIVE_INFINITY, 1.0));
+        assertTrue(MathUtils.equals(Double.NEGATIVE_INFINITY, 
Double.NEGATIVE_INFINITY, 1.0));
+        assertFalse(MathUtils.equals(Double.NEGATIVE_INFINITY, 
Double.POSITIVE_INFINITY, 1.0));
+        assertFalse(MathUtils.equals(153.0000, 153.0625, .0624));
+        assertFalse(MathUtils.equals(152.9374, 153.0000, .0625));
     }
     
     public void testArrayEquals() {