Test class for MathUtils with a test for binomialProbability().

git-svn-id: file:///humgen/gsa-scr1/gsa-engineering/svn_contents/trunk@519 348d0f76-0448-11de-a6fe-93d51630548a

java/test/org/broadinstitute/sting/utils/MathUtilsTest.java

@@ -0,0 +1,34 @@
+package org.broadinstitute.sting.utils;
+
+import org.junit.Assert;
+import org.junit.BeforeClass;
+import org.junit.Test;
+import org.broadinstitute.sting.BaseTest;
+import org.broadinstitute.sting.utils.MathUtils;
+
+
+import java.io.File;
+
+/**
+ * Basic unit test for MathUtils
+ */
+public class MathUtilsTest extends BaseTest {
+    @BeforeClass
+    public static void init() { }
+
+    /**
+     * Tests that we get the right values from the binomial distribution
+     */
+    @Test
+    public void testBinomialProbability() {
+        logger.warn("Executing testBinomialProbability");
+
+        Assert.assertTrue(MathUtils.compareDoubles(MathUtils.binomialProbability(2, 3, 0.5), 0.375, 0.001) == 0);
+        Assert.assertTrue(MathUtils.compareDoubles(MathUtils.binomialProbability(10, 100, 0.5), 1.365543e-17, 1e-18) == 0);
+        Assert.assertTrue(MathUtils.compareDoubles(MathUtils.binomialProbability(73, 217, 0.02), 4.521904e-67, 1e-68) == 0);
+        Assert.assertTrue(MathUtils.compareDoubles(MathUtils.binomialProbability(100, 300, 0.02), 9.27097e-91, 1e-92) == 0);
+        Assert.assertTrue(MathUtils.compareDoubles(MathUtils.binomialProbability(150, 300, 0.98), 6.462892e-168, 1e-169) == 0);
+        Assert.assertTrue(MathUtils.compareDoubles(MathUtils.binomialProbability(120, 300, 0.98), 3.090054e-221, 1e-222) == 0);
+        Assert.assertTrue(MathUtils.compareDoubles(MathUtils.binomialProbability(112, 300, 0.98), 2.34763e-236, 1e-237) == 0);
+    }
+}