commons-commits mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From l..@apache.org
Subject svn commit: r919172 - /commons/proper/math/trunk/src/test/java/org/apache/commons/math/ode/jacobians/FirstOrderIntegratorWithJacobiansTest.java
Date Thu, 04 Mar 2010 20:50:08 GMT
Author: luc
Date: Thu Mar  4 20:50:08 2010
New Revision: 919172

URL: http://svn.apache.org/viewvc?rev=919172&view=rev
Log:
explained test rationale

Modified:
    commons/proper/math/trunk/src/test/java/org/apache/commons/math/ode/jacobians/FirstOrderIntegratorWithJacobiansTest.java

Modified: commons/proper/math/trunk/src/test/java/org/apache/commons/math/ode/jacobians/FirstOrderIntegratorWithJacobiansTest.java
URL: http://svn.apache.org/viewvc/commons/proper/math/trunk/src/test/java/org/apache/commons/math/ode/jacobians/FirstOrderIntegratorWithJacobiansTest.java?rev=919172&r1=919171&r2=919172&view=diff
==============================================================================
--- commons/proper/math/trunk/src/test/java/org/apache/commons/math/ode/jacobians/FirstOrderIntegratorWithJacobiansTest.java
(original)
+++ commons/proper/math/trunk/src/test/java/org/apache/commons/math/ode/jacobians/FirstOrderIntegratorWithJacobiansTest.java
Thu Mar  4 20:50:08 2010
@@ -31,6 +31,15 @@
     @Test
     public void testLowAccuracyExternalDifferentiation()
         throws IntegratorException, DerivativeException {
+        // this test does not really test FirstOrderIntegratorWithJacobians,
+        // it only shows the WITHOUT this class, attempting to recover
+        // the jacobians from external differentiation on simple integration
+        // results with loo accuracy gives very poor results. In fact,
+        // the curves dy/dp = g(b) when b varies from 2.88 to 3.08 are
+        // essentially noise.
+        // This test is taken from Heirer, Norsett and Wanner book
+        // Solving Ordinary Differential Equations I (Nonstiff problems),
+        // the curves dy/dp = g(b) are in figure 6.5
         FirstOrderIntegrator integ =
             new DormandPrince54Integrator(1.0e-8, 100.0, 1.0e-4, 1.0e-4);
         double hP = 1.0e-12;



Mime
View raw message