use of org.hipparchus.analysis.differentiation.DerivativeStructure in project Orekit by CS-SI.
the class AbstractForceModelTest method checkStateJacobianVsFiniteDifferences.
protected void checkStateJacobianVsFiniteDifferences(final SpacecraftState state0, final ForceModel forceModel, final AttitudeProvider provider, final double dP, final double checkTolerance, final boolean print) throws OrekitException {
double[][] finiteDifferencesJacobian = Differentiation.differentiate(state -> forceModel.acceleration(state, forceModel.getParameters()).toArray(), 3, provider, OrbitType.CARTESIAN, PositionAngle.MEAN, dP, 5).value(state0);
DSFactory factory = new DSFactory(6, 1);
Field<DerivativeStructure> field = factory.getDerivativeField();
final FieldAbsoluteDate<DerivativeStructure> fDate = new FieldAbsoluteDate<>(field, state0.getDate());
final Vector3D p = state0.getPVCoordinates().getPosition();
final Vector3D v = state0.getPVCoordinates().getVelocity();
final Vector3D a = state0.getPVCoordinates().getAcceleration();
final TimeStampedFieldPVCoordinates<DerivativeStructure> fPVA = new TimeStampedFieldPVCoordinates<>(fDate, new FieldVector3D<>(factory.variable(0, p.getX()), factory.variable(1, p.getY()), factory.variable(2, p.getZ())), new FieldVector3D<>(factory.variable(3, v.getX()), factory.variable(4, v.getY()), factory.variable(5, v.getZ())), new FieldVector3D<>(factory.constant(a.getX()), factory.constant(a.getY()), factory.constant(a.getZ())));
final TimeStampedFieldAngularCoordinates<DerivativeStructure> fAC = new TimeStampedFieldAngularCoordinates<>(fDate, new FieldRotation<>(field, state0.getAttitude().getRotation()), new FieldVector3D<>(field, state0.getAttitude().getSpin()), new FieldVector3D<>(field, state0.getAttitude().getRotationAcceleration()));
final FieldSpacecraftState<DerivativeStructure> fState = new FieldSpacecraftState<>(new FieldCartesianOrbit<>(fPVA, state0.getFrame(), state0.getMu()), new FieldAttitude<>(state0.getFrame(), fAC), field.getZero().add(state0.getMass()));
FieldVector3D<DerivativeStructure> dsJacobian = forceModel.acceleration(fState, forceModel.getParameters(fState.getDate().getField()));
Vector3D dFdPXRef = new Vector3D(finiteDifferencesJacobian[0][0], finiteDifferencesJacobian[1][0], finiteDifferencesJacobian[2][0]);
Vector3D dFdPXRes = new Vector3D(dsJacobian.getX().getPartialDerivative(1, 0, 0, 0, 0, 0), dsJacobian.getY().getPartialDerivative(1, 0, 0, 0, 0, 0), dsJacobian.getZ().getPartialDerivative(1, 0, 0, 0, 0, 0));
Vector3D dFdPYRef = new Vector3D(finiteDifferencesJacobian[0][1], finiteDifferencesJacobian[1][1], finiteDifferencesJacobian[2][1]);
Vector3D dFdPYRes = new Vector3D(dsJacobian.getX().getPartialDerivative(0, 1, 0, 0, 0, 0), dsJacobian.getY().getPartialDerivative(0, 1, 0, 0, 0, 0), dsJacobian.getZ().getPartialDerivative(0, 1, 0, 0, 0, 0));
Vector3D dFdPZRef = new Vector3D(finiteDifferencesJacobian[0][2], finiteDifferencesJacobian[1][2], finiteDifferencesJacobian[2][2]);
Vector3D dFdPZRes = new Vector3D(dsJacobian.getX().getPartialDerivative(0, 0, 1, 0, 0, 0), dsJacobian.getY().getPartialDerivative(0, 0, 1, 0, 0, 0), dsJacobian.getZ().getPartialDerivative(0, 0, 1, 0, 0, 0));
Vector3D dFdVXRef = new Vector3D(finiteDifferencesJacobian[0][3], finiteDifferencesJacobian[1][3], finiteDifferencesJacobian[2][3]);
Vector3D dFdVXRes = new Vector3D(dsJacobian.getX().getPartialDerivative(0, 0, 0, 1, 0, 0), dsJacobian.getY().getPartialDerivative(0, 0, 0, 1, 0, 0), dsJacobian.getZ().getPartialDerivative(0, 0, 0, 1, 0, 0));
Vector3D dFdVYRef = new Vector3D(finiteDifferencesJacobian[0][4], finiteDifferencesJacobian[1][4], finiteDifferencesJacobian[2][4]);
Vector3D dFdVYRes = new Vector3D(dsJacobian.getX().getPartialDerivative(0, 0, 0, 0, 1, 0), dsJacobian.getY().getPartialDerivative(0, 0, 0, 0, 1, 0), dsJacobian.getZ().getPartialDerivative(0, 0, 0, 0, 1, 0));
Vector3D dFdVZRef = new Vector3D(finiteDifferencesJacobian[0][5], finiteDifferencesJacobian[1][5], finiteDifferencesJacobian[2][5]);
Vector3D dFdVZRes = new Vector3D(dsJacobian.getX().getPartialDerivative(0, 0, 0, 0, 0, 1), dsJacobian.getY().getPartialDerivative(0, 0, 0, 0, 0, 1), dsJacobian.getZ().getPartialDerivative(0, 0, 0, 0, 0, 1));
if (print) {
System.out.println("dF/dPX ref: " + dFdPXRef.getX() + " " + dFdPXRef.getY() + " " + dFdPXRef.getZ());
System.out.println("dF/dPX res: " + dFdPXRes.getX() + " " + dFdPXRes.getY() + " " + dFdPXRes.getZ());
System.out.println("dF/dPY ref: " + dFdPYRef.getX() + " " + dFdPYRef.getY() + " " + dFdPYRef.getZ());
System.out.println("dF/dPY res: " + dFdPYRes.getX() + " " + dFdPYRes.getY() + " " + dFdPYRes.getZ());
System.out.println("dF/dPZ ref: " + dFdPZRef.getX() + " " + dFdPZRef.getY() + " " + dFdPZRef.getZ());
System.out.println("dF/dPZ res: " + dFdPZRes.getX() + " " + dFdPZRes.getY() + " " + dFdPZRes.getZ());
System.out.println("dF/dPX ref norm: " + dFdPXRef.getNorm() + ", abs error: " + Vector3D.distance(dFdPXRef, dFdPXRes) + ", rel error: " + (Vector3D.distance(dFdPXRef, dFdPXRes) / dFdPXRef.getNorm()));
System.out.println("dF/dPY ref norm: " + dFdPYRef.getNorm() + ", abs error: " + Vector3D.distance(dFdPYRef, dFdPYRes) + ", rel error: " + (Vector3D.distance(dFdPYRef, dFdPYRes) / dFdPYRef.getNorm()));
System.out.println("dF/dPZ ref norm: " + dFdPZRef.getNorm() + ", abs error: " + Vector3D.distance(dFdPZRef, dFdPZRes) + ", rel error: " + (Vector3D.distance(dFdPZRef, dFdPZRes) / dFdPZRef.getNorm()));
System.out.println("dF/dVX ref norm: " + dFdVXRef.getNorm() + ", abs error: " + Vector3D.distance(dFdVXRef, dFdVXRes) + ", rel error: " + (Vector3D.distance(dFdVXRef, dFdVXRes) / dFdVXRef.getNorm()));
System.out.println("dF/dVY ref norm: " + dFdVYRef.getNorm() + ", abs error: " + Vector3D.distance(dFdVYRef, dFdVYRes) + ", rel error: " + (Vector3D.distance(dFdVYRef, dFdVYRes) / dFdVYRef.getNorm()));
System.out.println("dF/dVZ ref norm: " + dFdVZRef.getNorm() + ", abs error: " + Vector3D.distance(dFdVZRef, dFdVZRes) + ", rel error: " + (Vector3D.distance(dFdVZRef, dFdVZRes) / dFdVZRef.getNorm()));
}
checkdFdP(dFdPXRef, dFdPXRes, checkTolerance);
checkdFdP(dFdPYRef, dFdPYRes, checkTolerance);
checkdFdP(dFdPZRef, dFdPZRes, checkTolerance);
checkdFdP(dFdVXRef, dFdVXRes, checkTolerance);
checkdFdP(dFdVYRef, dFdVYRes, checkTolerance);
checkdFdP(dFdVZRef, dFdVZRes, checkTolerance);
}
use of org.hipparchus.analysis.differentiation.DerivativeStructure in project Orekit by CS-SI.
the class BoxAndSolarArraySpacecraftTest method testNormalOptimalRotationDS.
@Test
public void testNormalOptimalRotationDS() throws OrekitException {
AbsoluteDate initialDate = propagator.getInitialState().getDate();
CelestialBody sun = CelestialBodyFactory.getSun();
BoxAndSolarArraySpacecraft s = new BoxAndSolarArraySpacecraft(0, 0, 0, sun, 20.0, Vector3D.PLUS_J, 0.0, 1.0, 0.0);
DSFactory factory = new DSFactory(1, 2);
for (double dt = 0; dt < 4000; dt += 60) {
AbsoluteDate date = initialDate.shiftedBy(dt);
SpacecraftState state = propagator.propagate(date);
FieldVector3D<DerivativeStructure> normal = s.getNormal(state.getDate(), state.getFrame(), new FieldVector3D<>(factory.getDerivativeField(), state.getPVCoordinates().getPosition()), new FieldRotation<>(factory.getDerivativeField(), state.getAttitude().getRotation()));
Assert.assertEquals(0, FieldVector3D.dotProduct(normal, Vector3D.PLUS_J).getReal(), 1.0e-16);
}
}
use of org.hipparchus.analysis.differentiation.DerivativeStructure in project Orekit by CS-SI.
the class BoxAndSolarArraySpacecraftTest method testNormalFixedRateDS.
@Test
public void testNormalFixedRateDS() throws OrekitException {
AbsoluteDate initialDate = propagator.getInitialState().getDate();
CelestialBody sun = CelestialBodyFactory.getSun();
BoxAndSolarArraySpacecraft s = new BoxAndSolarArraySpacecraft(0, 0, 0, sun, 20.0, Vector3D.PLUS_J, initialDate, Vector3D.PLUS_K, 1.0e-3, 0.0, 1.0, 0.0);
DSFactory factory = new DSFactory(1, 2);
for (double dt = 0; dt < 4000; dt += 60) {
AbsoluteDate date = initialDate.shiftedBy(dt);
SpacecraftState state = propagator.propagate(date);
FieldVector3D<DerivativeStructure> normal = s.getNormal(state.getDate(), state.getFrame(), new FieldVector3D<>(factory.getDerivativeField(), state.getPVCoordinates().getPosition()), new FieldRotation<>(factory.getDerivativeField(), state.getAttitude().getRotation()));
Assert.assertEquals(0, FieldVector3D.dotProduct(normal, Vector3D.PLUS_J).getReal(), 1.0e-16);
}
}
use of org.hipparchus.analysis.differentiation.DerivativeStructure in project Orekit by CS-SI.
the class BoxAndSolarArraySpacecraftTest method testNullIllumination.
@Test
public void testNullIllumination() throws OrekitException {
SpacecraftState state = propagator.getInitialState();
CelestialBody sun = CelestialBodyFactory.getSun();
BoxAndSolarArraySpacecraft s = new BoxAndSolarArraySpacecraft(0, 0, 0, sun, 20.0, Vector3D.PLUS_J, 0.0, 1.0, 0.0);
FieldVector3D<DerivativeStructure> a = s.radiationPressureAcceleration(state.getDate(), state.getFrame(), state.getPVCoordinates().getPosition(), state.getAttitude().getRotation(), state.getMass(), new Vector3D(Precision.SAFE_MIN / 2, Vector3D.PLUS_I), getRadiationParameters(s), RadiationSensitive.ABSORPTION_COEFFICIENT);
Assert.assertEquals(0.0, a.getNorm().getReal(), Double.MIN_VALUE);
}
use of org.hipparchus.analysis.differentiation.DerivativeStructure in project Orekit by CS-SI.
the class NRLMSISE00Test method testDensityGradient.
@Test
public void testDensityGradient() throws OrekitException {
// Build the input params provider
final InputParams ip = new InputParams();
// Get Sun
final PVCoordinatesProvider sun = CelestialBodyFactory.getSun();
// Get Earth body shape
final Frame itrf = FramesFactory.getITRF(IERSConventions.IERS_2010, true);
final OneAxisEllipsoid earth = new OneAxisEllipsoid(Constants.WGS84_EARTH_EQUATORIAL_RADIUS, Constants.WGS84_EARTH_FLATTENING, itrf);
// Build the model
final NRLMSISE00 atm = new NRLMSISE00(ip, sun, earth);
// Build the date
final AbsoluteDate date = new AbsoluteDate(new DateComponents(2003, 172), new TimeComponents(29000.), TimeScalesFactory.getUT1(IERSConventions.IERS_2010, true));
// Build the position
final double alt = 400.;
final double lat = 60.;
final double lon = -70.;
final GeodeticPoint point = new GeodeticPoint(FastMath.toRadians(lat), FastMath.toRadians(lon), alt * 1000.);
final Vector3D pos = earth.transform(point);
// Run
DerivativeStructure zero = new DSFactory(1, 1).variable(0, 0.0);
FiniteDifferencesDifferentiator differentiator = new FiniteDifferencesDifferentiator(5, 10.0);
DerivativeStructure rhoX = differentiator.differentiate((double x) -> {
try {
return atm.getDensity(date, new Vector3D(1, pos, x, Vector3D.PLUS_I), itrf);
} catch (OrekitException oe) {
return Double.NaN;
}
}).value(zero);
DerivativeStructure rhoY = differentiator.differentiate((double y) -> {
try {
return atm.getDensity(date, new Vector3D(1, pos, y, Vector3D.PLUS_J), itrf);
} catch (OrekitException oe) {
return Double.NaN;
}
}).value(zero);
DerivativeStructure rhoZ = differentiator.differentiate((double z) -> {
try {
return atm.getDensity(date, new Vector3D(1, pos, z, Vector3D.PLUS_K), itrf);
} catch (OrekitException oe) {
return Double.NaN;
}
}).value(zero);
DSFactory factory3 = new DSFactory(3, 1);
Field<DerivativeStructure> field = factory3.getDerivativeField();
final DerivativeStructure rhoDS = atm.getDensity(new FieldAbsoluteDate<>(field, date), new FieldVector3D<>(factory3.variable(0, pos.getX()), factory3.variable(1, pos.getY()), factory3.variable(2, pos.getZ())), itrf);
Assert.assertEquals(rhoX.getValue(), rhoDS.getReal(), rhoX.getValue() * 2.0e-13);
Assert.assertEquals(rhoY.getValue(), rhoDS.getReal(), rhoY.getValue() * 2.0e-13);
Assert.assertEquals(rhoZ.getValue(), rhoDS.getReal(), rhoZ.getValue() * 2.0e-13);
Assert.assertEquals(rhoX.getPartialDerivative(1), rhoDS.getPartialDerivative(1, 0, 0), FastMath.abs(2.0e-10 * rhoX.getPartialDerivative(1)));
Assert.assertEquals(rhoY.getPartialDerivative(1), rhoDS.getPartialDerivative(0, 1, 0), FastMath.abs(2.0e-10 * rhoY.getPartialDerivative(1)));
Assert.assertEquals(rhoZ.getPartialDerivative(1), rhoDS.getPartialDerivative(0, 0, 1), FastMath.abs(2.0e-10 * rhoY.getPartialDerivative(1)));
}
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