protected <T extends RealFieldElement<T>> void doNonFieldInterpolatorConsistency(
final Field<T> field,
double epsilonSin,
double epsilonCos,
double epsilonSinDot,
double epsilonCosDot) {
FirstOrderFieldDifferentialEquations<T> eqn = new SinCos<T>(field);
RungeKuttaFieldStepInterpolator<T> fieldInterpolator =
setUpInterpolator(field, eqn, 0.0, new double[] {0.0, 1.0}, 0.125);
RungeKuttaStepInterpolator regularInterpolator = convertInterpolator(fieldInterpolator, eqn);
int n = 100;
double maxErrorSin = 0;
double maxErrorCos = 0;
double maxErrorSinDot = 0;
double maxErrorCosDot = 0;
for (int i = 0; i <= n; ++i) {
T t =
fieldInterpolator
.getPreviousState()
.getTime()
.multiply(n - i)
.add(fieldInterpolator.getCurrentState().getTime().multiply(i))
.divide(n);
FieldODEStateAndDerivative<T> state = fieldInterpolator.getInterpolatedState(t);
T[] fieldY = state.getState();
T[] fieldYDot = state.getDerivative();
regularInterpolator.setInterpolatedTime(t.getReal());
double[] regularY = regularInterpolator.getInterpolatedState();
double[] regularYDot = regularInterpolator.getInterpolatedDerivatives();
maxErrorSin = FastMath.max(maxErrorSin, fieldY[0].subtract(regularY[0]).abs().getReal());
maxErrorCos = FastMath.max(maxErrorCos, fieldY[1].subtract(regularY[1]).abs().getReal());
maxErrorSinDot =
FastMath.max(maxErrorSinDot, fieldYDot[0].subtract(regularYDot[0]).abs().getReal());
maxErrorCosDot =
FastMath.max(maxErrorCosDot, fieldYDot[1].subtract(regularYDot[1]).abs().getReal());
}
Assert.assertEquals(0.0, maxErrorSin, epsilonSin);
Assert.assertEquals(0.0, maxErrorCos, epsilonCos);
Assert.assertEquals(0.0, maxErrorSinDot, epsilonSinDot);
Assert.assertEquals(0.0, maxErrorCosDot, epsilonCosDot);
}
