Examples with StateFunction org.orekit.utils.StateFunction used on opensource projects

Example 6 with StateFunction

use of org.orekit.utils.StateFunction in project Orekit by CS-SI.

the class AngularAzElTest method testStateDerivatives.

@Test
public void testStateDerivatives() throws OrekitException {
    Context context = EstimationTestUtils.geoStationnaryContext("regular-data:potential:tides");
    final NumericalPropagatorBuilder propagatorBuilder = context.createBuilder(OrbitType.EQUINOCTIAL, PositionAngle.TRUE, false, 1.0e-6, 60.0, 0.001);
    // create perfect azimuth-elevation measurements
    final Propagator propagator = EstimationTestUtils.createPropagator(context.initialOrbit, propagatorBuilder);
    final List<ObservedMeasurement<?>> measurements = EstimationTestUtils.createMeasurements(propagator, new AngularAzElMeasurementCreator(context), 0.25, 3.0, 600.0);
    propagator.setSlaveMode();
    // Compute measurements.
    double[] AzerrorsP = new double[3 * measurements.size()];
    double[] AzerrorsV = new double[3 * measurements.size()];
    double[] ElerrorsP = new double[3 * measurements.size()];
    double[] ElerrorsV = new double[3 * measurements.size()];
    int AzindexP = 0;
    int AzindexV = 0;
    int ElindexP = 0;
    int ElindexV = 0;
    for (final ObservedMeasurement<?> measurement : measurements) {
        // parameter corresponding to station position offset
        final GroundStation stationParameter = ((AngularAzEl) measurement).getStation();
        // We intentionally propagate to a date which is close to the
        // real spacecraft state but is *not* the accurate date, by
        // compensating only part of the downlink delay. This is done
        // in order to validate the partial derivatives with respect
        // to velocity. If we had chosen the proper state date, the
        // angular would have depended only on the current position but
        // not on the current velocity.
        final AbsoluteDate datemeas = measurement.getDate();
        SpacecraftState state = propagator.propagate(datemeas);
        final Vector3D stationP = stationParameter.getOffsetToInertial(state.getFrame(), datemeas).transformPosition(Vector3D.ZERO);
        final double meanDelay = AbstractMeasurement.signalTimeOfFlight(state.getPVCoordinates(), stationP, datemeas);
        final AbsoluteDate date = measurement.getDate().shiftedBy(-0.75 * meanDelay);
        state = propagator.propagate(date);
        final EstimatedMeasurement<?> estimated = measurement.estimate(0, 0, new SpacecraftState[] { state });
        Assert.assertEquals(2, estimated.getParticipants().length);
        final double[][] jacobian = estimated.getStateDerivatives(0);
        // compute a reference value using finite differences
        final double[][] finiteDifferencesJacobian = Differentiation.differentiate(new StateFunction() {

            public double[] value(final SpacecraftState state) throws OrekitException {
                return measurement.estimate(0, 0, new SpacecraftState[] { state }).getEstimatedValue();
            }
        }, measurement.getDimension(), propagator.getAttitudeProvider(), OrbitType.CARTESIAN, PositionAngle.TRUE, 250.0, 4).value(state);
        Assert.assertEquals(finiteDifferencesJacobian.length, jacobian.length);
        Assert.assertEquals(finiteDifferencesJacobian[0].length, jacobian[0].length);
        final double smallest = FastMath.ulp((double) 1.0);
        for (int i = 0; i < jacobian.length; ++i) {
            for (int j = 0; j < jacobian[i].length; ++j) {
                double relativeError = FastMath.abs((finiteDifferencesJacobian[i][j] - jacobian[i][j]) / finiteDifferencesJacobian[i][j]);
                if ((FastMath.sqrt(finiteDifferencesJacobian[i][j]) < smallest) && (FastMath.sqrt(jacobian[i][j]) < smallest)) {
                    relativeError = 0.0;
                }
                if (j < 3) {
                    if (i == 0) {
                        AzerrorsP[AzindexP++] = relativeError;
                    } else {
                        ElerrorsP[ElindexP++] = relativeError;
                    }
                } else {
                    if (i == 0) {
                        AzerrorsV[AzindexV++] = relativeError;
                    } else {
                        ElerrorsV[ElindexV++] = relativeError;
                    }
                }
            }
        }
    }
    // median errors on Azimuth
    Assert.assertEquals(0.0, new Median().evaluate(AzerrorsP), 1.1e-10);
    Assert.assertEquals(0.0, new Median().evaluate(AzerrorsV), 5.7e-5);
    // median errors on Elevation
    Assert.assertEquals(0.0, new Median().evaluate(ElerrorsP), 3.5e-11);
    Assert.assertEquals(0.0, new Median().evaluate(ElerrorsV), 1.4e-5);
}

Example 7 with StateFunction

use of org.orekit.utils.StateFunction in project Orekit by CS-SI.

the class TurnAroundRangeAnalyticTest method genericTestStateDerivatives.

/**
 * Generic test function for derivatives with respect to state
 * @param isModifier Use of atmospheric modifiers
 * @param isFiniteDifferences Finite differences reference calculation if true, TurnAroundRange class otherwise
 * @param printResults Print the results ?
 * @throws OrekitException
 */
void genericTestStateDerivatives(final boolean isModifier, final boolean isFiniteDifferences, final boolean printResults, final double refErrorsPMedian, final double refErrorsPMean, final double refErrorsPMax, final double refErrorsVMedian, final double refErrorsVMean, final double refErrorsVMax) throws OrekitException {
    Context context = EstimationTestUtils.eccentricContext("regular-data:potential:tides");
    // Context context = EstimationTestUtils.geoStationnaryContext();
    final NumericalPropagatorBuilder propagatorBuilder = context.createBuilder(OrbitType.KEPLERIAN, PositionAngle.TRUE, true, 1.0e-6, 60.0, 0.001);
    // create perfect range2 measurements
    final Propagator propagator = EstimationTestUtils.createPropagator(context.initialOrbit, propagatorBuilder);
    final List<ObservedMeasurement<?>> measurements = EstimationTestUtils.createMeasurements(propagator, new TurnAroundRangeMeasurementCreator(context), 1.0, 3.0, 300.0);
    propagator.setSlaveMode();
    double[] errorsP = new double[3 * measurements.size()];
    double[] errorsV = new double[3 * measurements.size()];
    int indexP = 0;
    int indexV = 0;
    // Print the results ? Header
    if (printResults) {
        System.out.format(Locale.US, "%-15s  %-15s  %-23s  %-23s  " + "%10s  %10s  %10s  " + "%10s  %10s  %10s  " + "%10s  %10s  %10s  " + "%10s  %10s  %10s%n", "Master Station", "Slave Station", "Measurement Date", "State Date", "ΔdPx", "ΔdPy", "ΔdPz", "ΔdVx", "ΔdVy", "ΔdVz", "rel ΔdPx", "rel ΔdPy", "rel ΔdPz", "rel ΔdVx", "rel ΔdVy", "rel ΔdVz");
    }
    // Loop on the measurements
    for (final ObservedMeasurement<?> measurement : measurements) {
        // Add modifiers if test implies it
        final TurnAroundRangeTroposphericDelayModifier modifier = new TurnAroundRangeTroposphericDelayModifier(SaastamoinenModel.getStandardModel());
        if (isModifier) {
            ((TurnAroundRange) measurement).addModifier(modifier);
        }
        // We intentionally propagate to a date which is close to the
        // real spacecraft state but is *not* the accurate date, by
        // compensating only part of the downlink delay. This is done
        // in order to validate the partial derivatives with respect
        // to velocity. If we had chosen the proper state date, the
        // range would have depended only on the current position but
        // not on the current velocity.
        final double meanDelay = measurement.getObservedValue()[0] / Constants.SPEED_OF_LIGHT;
        final AbsoluteDate date = measurement.getDate().shiftedBy(-0.75 * meanDelay);
        final SpacecraftState state = propagator.propagate(date);
        final EstimatedMeasurement<TurnAroundRange> TAR = new TurnAroundRangeAnalytic((TurnAroundRange) measurement).theoreticalEvaluationAnalytic(0, 0, propagator.getInitialState(), state);
        if (isModifier) {
            modifier.modify(TAR);
        }
        final double[][] jacobian = TAR.getStateDerivatives(0);
        // Jacobian reference value
        final double[][] jacobianRef;
        if (isFiniteDifferences) {
            // Compute a reference value using finite differences
            jacobianRef = Differentiation.differentiate(new StateFunction() {

                public double[] value(final SpacecraftState state) throws OrekitException {
                    return measurement.estimate(0, 0, new SpacecraftState[] { state }).getEstimatedValue();
                }
            }, measurement.getDimension(), propagator.getAttitudeProvider(), OrbitType.CARTESIAN, PositionAngle.TRUE, 2.0, 3).value(state);
        } else {
            // Compute a reference value using TurnAroundRange class function
            jacobianRef = ((TurnAroundRange) measurement).theoreticalEvaluation(0, 0, new SpacecraftState[] { state }).getStateDerivatives(0);
        }
        // //Test: Test point by point with the debugger
        // if (!isFiniteDifferences && !isModifier) {
        // final EstimatedMeasurement<TurnAroundRange> test =
        // new TurnAroundRangeAnalytic((TurnAroundRange)measurement).theoreticalEvaluationValidation(0, 0, state);
        // }
        // //Test
        Assert.assertEquals(jacobianRef.length, jacobian.length);
        Assert.assertEquals(jacobianRef[0].length, jacobian[0].length);
        double[][] dJacobian = new double[jacobian.length][jacobian[0].length];
        double[][] dJacobianRelative = new double[jacobian.length][jacobian[0].length];
        for (int i = 0; i < jacobian.length; ++i) {
            for (int j = 0; j < jacobian[i].length; ++j) {
                dJacobian[i][j] = jacobian[i][j] - jacobianRef[i][j];
                dJacobianRelative[i][j] = FastMath.abs(dJacobian[i][j] / jacobianRef[i][j]);
                if (j < 3) {
                    errorsP[indexP++] = dJacobianRelative[i][j];
                } else {
                    errorsV[indexV++] = dJacobianRelative[i][j];
                }
            }
        }
        // Print results on the console ? Print the Jacobian
        if (printResults) {
            String masterStationName = ((TurnAroundRange) measurement).getMasterStation().getBaseFrame().getName();
            String slaveStationName = ((TurnAroundRange) measurement).getSlaveStation().getBaseFrame().getName();
            System.out.format(Locale.US, "%-15s  %-15s  %-23s  %-23s  " + "%10.3e  %10.3e  %10.3e  " + "%10.3e  %10.3e  %10.3e  " + "%10.3e  %10.3e  %10.3e  " + "%10.3e  %10.3e  %10.3e%n", masterStationName, slaveStationName, measurement.getDate(), date, dJacobian[0][0], dJacobian[0][1], dJacobian[0][2], dJacobian[0][3], dJacobian[0][4], dJacobian[0][5], dJacobianRelative[0][0], dJacobianRelative[0][1], dJacobianRelative[0][2], dJacobianRelative[0][3], dJacobianRelative[0][4], dJacobianRelative[0][5]);
        }
    }
    // End loop on the measurements
    // Compute some statistics
    final double errorsPMedian = new Median().evaluate(errorsP);
    final double errorsPMean = new Mean().evaluate(errorsP);
    final double errorsPMax = new Max().evaluate(errorsP);
    final double errorsVMedian = new Median().evaluate(errorsV);
    final double errorsVMean = new Mean().evaluate(errorsV);
    final double errorsVMax = new Max().evaluate(errorsV);
    // Print the results on console ? Final results
    if (printResults) {
        System.out.println();
        System.out.format(Locale.US, "Relative errors dR/dP -> Median: %6.3e / Mean: %6.3e / Max: %6.3e%n", errorsPMedian, errorsPMean, errorsPMax);
        System.out.format(Locale.US, "Relative errors dR/dV -> Median: %6.3e / Mean: %6.3e / Max: %6.3e%n", errorsVMedian, errorsVMean, errorsVMax);
    }
    // Assert the results / max values depend on the test
    Assert.assertEquals(0.0, errorsPMedian, refErrorsPMedian);
    Assert.assertEquals(0.0, errorsPMean, refErrorsPMean);
    Assert.assertEquals(0.0, errorsPMax, refErrorsPMax);
    Assert.assertEquals(0.0, errorsVMedian, refErrorsVMedian);
    Assert.assertEquals(0.0, errorsVMean, refErrorsVMean);
    Assert.assertEquals(0.0, errorsVMax, refErrorsVMax);
}

Example 8 with StateFunction

use of org.orekit.utils.StateFunction in project Orekit by CS-SI.

the class PVTest method testStateDerivatives.

@Test
public void testStateDerivatives() throws OrekitException {
    Context context = EstimationTestUtils.eccentricContext("regular-data:potential:tides");
    final NumericalPropagatorBuilder propagatorBuilder = context.createBuilder(OrbitType.KEPLERIAN, PositionAngle.TRUE, true, 1.0e-6, 60.0, 0.001);
    // create perfect range measurements
    final Propagator propagator = EstimationTestUtils.createPropagator(context.initialOrbit, propagatorBuilder);
    final List<ObservedMeasurement<?>> measurements = EstimationTestUtils.createMeasurements(propagator, new PVMeasurementCreator(), 1.0, 3.0, 300.0);
    propagator.setSlaveMode();
    double[] errorsP = new double[3 * 6 * measurements.size()];
    double[] errorsV = new double[3 * 6 * measurements.size()];
    int indexP = 0;
    int indexV = 0;
    for (final ObservedMeasurement<?> measurement : measurements) {
        final AbsoluteDate date = measurement.getDate();
        final SpacecraftState state = propagator.propagate(date);
        final double[][] jacobian = measurement.estimate(0, 0, new SpacecraftState[] { state }).getStateDerivatives(0);
        // compute a reference value using finite differences
        final double[][] finiteDifferencesJacobian = Differentiation.differentiate(new StateFunction() {

            public double[] value(final SpacecraftState state) throws OrekitException {
                return measurement.estimate(0, 0, new SpacecraftState[] { state }).getEstimatedValue();
            }
        }, measurement.getDimension(), propagator.getAttitudeProvider(), OrbitType.CARTESIAN, PositionAngle.TRUE, 1.0, 3).value(state);
        Assert.assertEquals(finiteDifferencesJacobian.length, jacobian.length);
        Assert.assertEquals(finiteDifferencesJacobian[0].length, jacobian[0].length);
        for (int i = 0; i < jacobian.length; ++i) {
            for (int j = 0; j < jacobian[i].length; ++j) {
                final double relativeError = FastMath.abs((finiteDifferencesJacobian[i][j] - jacobian[i][j]) / finiteDifferencesJacobian[i][j]);
                if (j < 3) {
                    errorsP[indexP++] = relativeError;
                } else {
                    errorsV[indexV++] = relativeError;
                }
            }
        }
    }
    // median errors
    Assert.assertEquals(0.0, new Median().evaluate(errorsP), 2.1e-10);
    Assert.assertEquals(0.0, new Median().evaluate(errorsV), 2.1e-10);
}

Example 9 with StateFunction

use of org.orekit.utils.StateFunction in project Orekit by CS-SI.

the class RangeRateTest method testStateDerivativesWithModifier.

@Test
public void testStateDerivativesWithModifier() throws OrekitException {
    Context context = EstimationTestUtils.eccentricContext("regular-data:potential:tides");
    final NumericalPropagatorBuilder propagatorBuilder = context.createBuilder(OrbitType.KEPLERIAN, PositionAngle.TRUE, true, 1.0e-6, 60.0, 0.001);
    // create perfect range rate measurements
    final Propagator propagator = EstimationTestUtils.createPropagator(context.initialOrbit, propagatorBuilder);
    final List<ObservedMeasurement<?>> measurements = EstimationTestUtils.createMeasurements(propagator, new RangeRateMeasurementCreator(context, false), 1.0, 3.0, 300.0);
    propagator.setSlaveMode();
    double maxRelativeError = 0;
    for (final ObservedMeasurement<?> measurement : measurements) {
        final RangeRateTroposphericDelayModifier modifier = new RangeRateTroposphericDelayModifier(SaastamoinenModel.getStandardModel(), true);
        ((RangeRate) measurement).addModifier(modifier);
        // 
        // final AbsoluteDate date = measurement.getDate();
        // measurement.getObservedValue()[0] / Constants.SPEED_OF_LIGHT;
        final double meanDelay = 1;
        final AbsoluteDate date = measurement.getDate().shiftedBy(-0.75 * meanDelay);
        final SpacecraftState state = propagator.propagate(date);
        final double[][] jacobian = measurement.estimate(0, 0, new SpacecraftState[] { state }).getStateDerivatives(0);
        final double[][] finiteDifferencesJacobian = Differentiation.differentiate(new StateFunction() {

            public double[] value(final SpacecraftState state) throws OrekitException {
                return measurement.estimate(0, 0, new SpacecraftState[] { state }).getEstimatedValue();
            }
        }, 1, propagator.getAttitudeProvider(), OrbitType.CARTESIAN, PositionAngle.TRUE, 15.0, 3).value(state);
        Assert.assertEquals(finiteDifferencesJacobian.length, jacobian.length);
        Assert.assertEquals(finiteDifferencesJacobian[0].length, jacobian[0].length);
        for (int i = 0; i < jacobian.length; ++i) {
            for (int j = 0; j < jacobian[i].length; ++j) {
                // check the values returned by getStateDerivatives() are correct
                maxRelativeError = FastMath.max(maxRelativeError, FastMath.abs((finiteDifferencesJacobian[i][j] - jacobian[i][j]) / finiteDifferencesJacobian[i][j]));
            }
        }
    }
    Assert.assertEquals(0, maxRelativeError, 1.5e-7);
}

Example 10 with StateFunction

use of org.orekit.utils.StateFunction in project Orekit by CS-SI.

the class RangeRateTest method testStateDerivativesTwoWays.

@Test
public void testStateDerivativesTwoWays() throws OrekitException {
    Context context = EstimationTestUtils.eccentricContext("regular-data:potential:tides");
    final NumericalPropagatorBuilder propagatorBuilder = context.createBuilder(OrbitType.KEPLERIAN, PositionAngle.TRUE, true, 1.0e-6, 60.0, 0.001);
    // create perfect range rate measurements
    final Propagator propagator = EstimationTestUtils.createPropagator(context.initialOrbit, propagatorBuilder);
    final List<ObservedMeasurement<?>> measurements = EstimationTestUtils.createMeasurements(propagator, new RangeRateMeasurementCreator(context, true), 1.0, 3.0, 300.0);
    for (final ObservedMeasurement<?> m : measurements) {
        Assert.assertTrue(((RangeRate) m).isTwoWay());
    }
    propagator.setSlaveMode();
    double maxRelativeError = 0;
    for (final ObservedMeasurement<?> measurement : measurements) {
        // 
        // final AbsoluteDate date = measurement.getDate();
        // measurement.getObservedValue()[0] / Constants.SPEED_OF_LIGHT;
        final double meanDelay = 1;
        final AbsoluteDate date = measurement.getDate().shiftedBy(-0.75 * meanDelay);
        final SpacecraftState state = propagator.propagate(date);
        final EstimatedMeasurement<?> estimated = measurement.estimate(0, 0, new SpacecraftState[] { state });
        Assert.assertEquals(3, estimated.getParticipants().length);
        final double[][] jacobian = estimated.getStateDerivatives(0);
        final double[][] finiteDifferencesJacobian = Differentiation.differentiate(new StateFunction() {

            public double[] value(final SpacecraftState state) throws OrekitException {
                return measurement.estimate(0, 0, new SpacecraftState[] { state }).getEstimatedValue();
            }
        }, 1, propagator.getAttitudeProvider(), OrbitType.CARTESIAN, PositionAngle.TRUE, 15.0, 3).value(state);
        Assert.assertEquals(finiteDifferencesJacobian.length, jacobian.length);
        Assert.assertEquals(finiteDifferencesJacobian[0].length, jacobian[0].length);
        for (int i = 0; i < jacobian.length; ++i) {
            for (int j = 0; j < jacobian[i].length; ++j) {
                // check the values returned by getStateDerivatives() are correct
                maxRelativeError = FastMath.max(maxRelativeError, FastMath.abs((finiteDifferencesJacobian[i][j] - jacobian[i][j]) / finiteDifferencesJacobian[i][j]));
            }
        }
    }
    Assert.assertEquals(0, maxRelativeError, 2.6e-5);
}