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Posted to commits@commons.apache.org by lu...@apache.org on 2010/06/06 15:59:06 UTC
svn commit: r951863 -
/commons/proper/math/trunk/src/test/java/org/apache/commons/math/optimization/fitting/CurveFitterTest.java
Author: luc
Date: Sun Jun 6 13:59:06 2010
New Revision: 951863
URL: http://svn.apache.org/viewvc?rev=951863&view=rev
Log:
added a test derived from an invalid issue
Modified:
commons/proper/math/trunk/src/test/java/org/apache/commons/math/optimization/fitting/CurveFitterTest.java
Modified: commons/proper/math/trunk/src/test/java/org/apache/commons/math/optimization/fitting/CurveFitterTest.java
URL: http://svn.apache.org/viewvc/commons/proper/math/trunk/src/test/java/org/apache/commons/math/optimization/fitting/CurveFitterTest.java?rev=951863&r1=951862&r2=951863&view=diff
==============================================================================
--- commons/proper/math/trunk/src/test/java/org/apache/commons/math/optimization/fitting/CurveFitterTest.java (original)
+++ commons/proper/math/trunk/src/test/java/org/apache/commons/math/optimization/fitting/CurveFitterTest.java Sun Jun 6 13:59:06 2010
@@ -72,6 +72,70 @@ public class CurveFitterTest {
}
+ @Test
+ public void testMath372()
+ throws OptimizationException, FunctionEvaluationException {
+ LevenbergMarquardtOptimizer optimizer = new LevenbergMarquardtOptimizer();
+ CurveFitter curveFitter = new CurveFitter(optimizer);
+
+ curveFitter.addObservedPoint( 15, 4443);
+ curveFitter.addObservedPoint( 31, 8493);
+ curveFitter.addObservedPoint( 62, 17586);
+ curveFitter.addObservedPoint(125, 30582);
+ curveFitter.addObservedPoint(250, 45087);
+ curveFitter.addObservedPoint(500, 50683);
+
+ ParametricRealFunction f = new ParametricRealFunction() {
+
+ public double value(double x, double[] parameters) {
+
+ double a = parameters[0];
+ double b = parameters[1];
+ double c = parameters[2];
+ double d = parameters[3];
+
+ return d + ((a - d) / (1 + Math.pow(x / c, b)));
+ }
+
+ public double[] gradient(double x, double[] parameters) {
+
+ double a = parameters[0];
+ double b = parameters[1];
+ double c = parameters[2];
+ double d = parameters[3];
+
+ double[] gradients = new double[4];
+ double den = 1 + Math.pow(x / c, b);
+
+ // derivative with respect to a
+ gradients[0] = 1 / den;
+
+ // derivative with respect to b
+ // in the reported (invalid) issue, there was a sign error here
+ gradients[1] = -((a - d) * Math.pow(x / c, b) * Math.log(x / c)) / (den * den);
+
+ // derivative with respect to c
+ gradients[2] = (b * Math.pow(x / c, b - 1) * (x / (c * c)) * (a - d)) / (den * den);
+
+ // derivative with respect to d
+ gradients[3] = 1 - (1 / den);
+
+ return gradients;
+
+ }
+ };
+
+ double[] initialGuess = new double[] { 1500, 0.95, 65, 35000 };
+ double[] estimatedParameters = curveFitter.fit(f, initialGuess);
+
+ Assert.assertEquals( 2411.00, estimatedParameters[0], 500.00);
+ Assert.assertEquals( 1.62, estimatedParameters[1], 0.04);
+ Assert.assertEquals( 111.22, estimatedParameters[2], 0.30);
+ Assert.assertEquals(55347.47, estimatedParameters[3], 300.00);
+ Assert.assertTrue(optimizer.getRMS() < 600.0);
+
+ }
+
private static class SimpleInverseFunction implements ParametricRealFunction {
public double value(double x, double[] parameters) {