The full set of derivatives are needed in Runge-Kutta.

2016-01-06 12:24:24 +01:00 · 2016-01-06 12:24:24 +01:00 · b21b4c8ded
parent c4e2ddf266
commit b21b4c8ded
1 changed files with 1 additions and 1 deletions
--- a/src/main/java/org/apache/commons/math4/ode/nonstiff/RungeKuttaFieldIntegrator.java
+++ b/src/main/java/org/apache/commons/math4/ode/nonstiff/RungeKuttaFieldIntegrator.java
@ -143,7 +143,7 @@ public abstract class RungeKuttaFieldIntegrator<T extends RealFieldElement<T>>
            interpolator.shift();

            // first stage
-            yDotK[0] = stepStart.getDerivative();
+            yDotK[0] = equations.getMapper().mapDerivative(stepStart);

            // next stages
            for (int k = 1; k < stages; ++k) {