use of org.hipparchus.linear.RealMatrix in project symja_android_library by axkr.
the class Roots method findRoots.
/**
* <p>
* Given a set of polynomial coefficients, compute the roots of the
* polynomial. Depending on the polynomial being considered the roots may
* contain complex number. When complex numbers are present they will come
* in pairs of complex conjugates.
* </p>
*
* @param coefficients
* coefficients of the polynomial.
* @return the roots of the polynomial
*/
@Nonnull
public static IAST findRoots(double... coefficients) {
int N = coefficients.length - 1;
// Construct the companion matrix
RealMatrix c = new Array2DRowRealMatrix(N, N);
double a = coefficients[N];
for (int i = 0; i < N; i++) {
c.setEntry(i, N - 1, -coefficients[i] / a);
}
for (int i = 1; i < N; i++) {
c.setEntry(i, i - 1, 1);
}
try {
IAST roots = F.List();
EigenDecomposition ed = new EigenDecomposition(c);
double[] realValues = ed.getRealEigenvalues();
double[] imagValues = ed.getImagEigenvalues();
for (int i = 0; i < N; i++) {
roots.append(F.chopExpr(F.complexNum(realValues[i], imagValues[i]), Config.DEFAULT_ROOTS_CHOP_DELTA));
}
return roots;
} catch (Exception ime) {
throw new WrappedException(ime);
}
}
use of org.hipparchus.linear.RealMatrix in project Orekit by CS-SI.
the class BatchLSEstimatorTest method testKeplerPV.
/**
* Perfect PV measurements with a perfect start
* @throws OrekitException
*/
@Test
public void testKeplerPV() 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, 1.0);
// create perfect PV measurements
final Propagator propagator = EstimationTestUtils.createPropagator(context.initialOrbit, propagatorBuilder);
final List<ObservedMeasurement<?>> measurements = EstimationTestUtils.createMeasurements(propagator, new PVMeasurementCreator(), 0.0, 1.0, 300.0);
// create orbit estimator
final BatchLSEstimator estimator = new BatchLSEstimator(new LevenbergMarquardtOptimizer(), propagatorBuilder);
for (final ObservedMeasurement<?> measurement : measurements) {
estimator.addMeasurement(measurement);
}
estimator.setParametersConvergenceThreshold(1.0e-2);
estimator.setMaxIterations(10);
estimator.setMaxEvaluations(20);
EstimationTestUtils.checkFit(context, estimator, 1, 4, 0.0, 2.2e-8, 0.0, 1.1e-7, 0.0, 1.4e-8, 0.0, 6.3e-12);
RealMatrix normalizedCovariances = estimator.getOptimum().getCovariances(1.0e-10);
RealMatrix physicalCovariances = estimator.getPhysicalCovariances(1.0e-10);
Assert.assertEquals(6, normalizedCovariances.getRowDimension());
Assert.assertEquals(6, normalizedCovariances.getColumnDimension());
Assert.assertEquals(6, physicalCovariances.getRowDimension());
Assert.assertEquals(6, physicalCovariances.getColumnDimension());
Assert.assertEquals(0.00258, physicalCovariances.getEntry(0, 0), 1.0e-5);
}
use of org.hipparchus.linear.RealMatrix in project Orekit by CS-SI.
the class GroundStationTest method testEstimateStationPosition.
@Test
public void testEstimateStationPosition() throws OrekitException, IOException, ClassNotFoundException {
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 RangeMeasurementCreator(context), 1.0, 3.0, 300.0);
// move one station
final RandomGenerator random = new Well19937a(0x4adbecfc743bda60l);
final TopocentricFrame base = context.stations.get(0).getBaseFrame();
final BodyShape parent = base.getParentShape();
final Vector3D baseOrigin = parent.transform(base.getPoint());
final Vector3D deltaTopo = new Vector3D(2 * random.nextDouble() - 1, 2 * random.nextDouble() - 1, 2 * random.nextDouble() - 1);
final Transform topoToParent = base.getTransformTo(parent.getBodyFrame(), (AbsoluteDate) null);
final Vector3D deltaParent = topoToParent.transformVector(deltaTopo);
final String movedSuffix = "-moved";
final GroundStation moved = new GroundStation(new TopocentricFrame(parent, parent.transform(baseOrigin.subtract(deltaParent), parent.getBodyFrame(), null), base.getName() + movedSuffix), context.ut1.getEOPHistory(), context.stations.get(0).getDisplacements());
// create orbit estimator
final BatchLSEstimator estimator = new BatchLSEstimator(new LevenbergMarquardtOptimizer(), propagatorBuilder);
for (final ObservedMeasurement<?> measurement : measurements) {
final Range range = (Range) measurement;
final String name = range.getStation().getBaseFrame().getName() + movedSuffix;
if (moved.getBaseFrame().getName().equals(name)) {
estimator.addMeasurement(new Range(moved, range.getDate(), range.getObservedValue()[0], range.getTheoreticalStandardDeviation()[0], range.getBaseWeight()[0]));
} else {
estimator.addMeasurement(range);
}
}
estimator.setParametersConvergenceThreshold(1.0e-3);
estimator.setMaxIterations(100);
estimator.setMaxEvaluations(200);
// we want to estimate station offsets
moved.getEastOffsetDriver().setSelected(true);
moved.getNorthOffsetDriver().setSelected(true);
moved.getZenithOffsetDriver().setSelected(true);
EstimationTestUtils.checkFit(context, estimator, 2, 3, 0.0, 5.6e-7, 0.0, 1.4e-6, 0.0, 4.8e-7, 0.0, 2.6e-10);
Assert.assertEquals(deltaTopo.getX(), moved.getEastOffsetDriver().getValue(), 4.5e-7);
Assert.assertEquals(deltaTopo.getY(), moved.getNorthOffsetDriver().getValue(), 6.2e-7);
Assert.assertEquals(deltaTopo.getZ(), moved.getZenithOffsetDriver().getValue(), 2.6e-7);
GeodeticPoint result = moved.getOffsetGeodeticPoint(null);
GeodeticPoint reference = context.stations.get(0).getBaseFrame().getPoint();
Assert.assertEquals(reference.getLatitude(), result.getLatitude(), 1.4e-14);
Assert.assertEquals(reference.getLongitude(), result.getLongitude(), 2.9e-14);
Assert.assertEquals(reference.getAltitude(), result.getAltitude(), 2.6e-7);
RealMatrix normalizedCovariances = estimator.getOptimum().getCovariances(1.0e-10);
RealMatrix physicalCovariances = estimator.getPhysicalCovariances(1.0e-10);
Assert.assertEquals(9, normalizedCovariances.getRowDimension());
Assert.assertEquals(9, normalizedCovariances.getColumnDimension());
Assert.assertEquals(9, physicalCovariances.getRowDimension());
Assert.assertEquals(9, physicalCovariances.getColumnDimension());
Assert.assertEquals(0.55431, physicalCovariances.getEntry(6, 6), 1.0e-5);
Assert.assertEquals(0.22694, physicalCovariances.getEntry(7, 7), 1.0e-5);
Assert.assertEquals(0.13106, physicalCovariances.getEntry(8, 8), 1.0e-5);
ByteArrayOutputStream bos = new ByteArrayOutputStream();
ObjectOutputStream oos = new ObjectOutputStream(bos);
oos.writeObject(moved.getEstimatedEarthFrame().getTransformProvider());
Assert.assertTrue(bos.size() > 155000);
Assert.assertTrue(bos.size() < 160000);
ByteArrayInputStream bis = new ByteArrayInputStream(bos.toByteArray());
ObjectInputStream ois = new ObjectInputStream(bis);
EstimatedEarthFrameProvider deserialized = (EstimatedEarthFrameProvider) ois.readObject();
Assert.assertEquals(moved.getPrimeMeridianOffsetDriver().getValue(), deserialized.getPrimeMeridianOffsetDriver().getValue(), 1.0e-15);
Assert.assertEquals(moved.getPrimeMeridianDriftDriver().getValue(), deserialized.getPrimeMeridianDriftDriver().getValue(), 1.0e-15);
Assert.assertEquals(moved.getPolarOffsetXDriver().getValue(), deserialized.getPolarOffsetXDriver().getValue(), 1.0e-15);
Assert.assertEquals(moved.getPolarDriftXDriver().getValue(), deserialized.getPolarDriftXDriver().getValue(), 1.0e-15);
Assert.assertEquals(moved.getPolarOffsetYDriver().getValue(), deserialized.getPolarOffsetYDriver().getValue(), 1.0e-15);
Assert.assertEquals(moved.getPolarDriftYDriver().getValue(), deserialized.getPolarDriftYDriver().getValue(), 1.0e-15);
}
use of org.hipparchus.linear.RealMatrix in project Orekit by CS-SI.
the class KalmanEstimatorTest method testKeplerianRangeAzElAndRangeRate.
/**
* Perfect Range, Azel and range rate measurements with a biased start
* Start: position/velocity biased with: [+1000,0,0] m and [0,0,0.01] m/s
* Keplerian formalism
*/
@Test
public void testKeplerianRangeAzElAndRangeRate() throws OrekitException {
// Create context
Context context = EstimationTestUtils.eccentricContext("regular-data:potential:tides");
// Create initial orbit and propagator builder
final OrbitType orbitType = OrbitType.KEPLERIAN;
final PositionAngle positionAngle = PositionAngle.TRUE;
final boolean perfectStart = true;
final double minStep = 1.e-6;
final double maxStep = 60.;
final double dP = 1.;
final NumericalPropagatorBuilder measPropagatorBuilder = context.createBuilder(orbitType, positionAngle, perfectStart, minStep, maxStep, dP);
// Create perfect range measurements
final Propagator rangePropagator = EstimationTestUtils.createPropagator(context.initialOrbit, measPropagatorBuilder);
final List<ObservedMeasurement<?>> rangeMeasurements = EstimationTestUtils.createMeasurements(rangePropagator, new RangeMeasurementCreator(context), 0.0, 4.0, 300.0);
// Create perfect az/el measurements
final Propagator angularPropagator = EstimationTestUtils.createPropagator(context.initialOrbit, measPropagatorBuilder);
final List<ObservedMeasurement<?>> angularMeasurements = EstimationTestUtils.createMeasurements(angularPropagator, new AngularAzElMeasurementCreator(context), 0.0, 4.0, 500.0);
// Create perfect range rate measurements
final Propagator rangeRatePropagator = EstimationTestUtils.createPropagator(context.initialOrbit, measPropagatorBuilder);
final List<ObservedMeasurement<?>> rangeRateMeasurements = EstimationTestUtils.createMeasurements(rangeRatePropagator, new RangeRateMeasurementCreator(context, false), 0.0, 4.0, 700.0);
// Concatenate measurements
final List<ObservedMeasurement<?>> measurements = new ArrayList<ObservedMeasurement<?>>();
measurements.addAll(rangeMeasurements);
measurements.addAll(angularMeasurements);
measurements.addAll(rangeRateMeasurements);
measurements.sort(new ChronologicalComparator());
// Reference propagator for estimation performances
final NumericalPropagator referencePropagator = measPropagatorBuilder.buildPropagator(measPropagatorBuilder.getSelectedNormalizedParameters());
// Reference position/velocity at last measurement date
final Orbit refOrbit = referencePropagator.propagate(measurements.get(measurements.size() - 1).getDate()).getOrbit();
// Biased propagator for the Kalman
final NumericalPropagatorBuilder propagatorBuilder = context.createBuilder(orbitType, positionAngle, false, minStep, maxStep, dP);
// Cartesian covariance matrix initialization
// Initial sigmas: 1000m on position, 0.01m/s on velocity
final RealMatrix cartesianP = MatrixUtils.createRealDiagonalMatrix(new double[] { 1e6, 1e6, 1e6, 1e-4, 1e-4, 1e-4 });
// Jacobian of the orbital parameters w/r to Cartesian
final Orbit initialOrbit = orbitType.convertType(context.initialOrbit);
final double[][] dYdC = new double[6][6];
initialOrbit.getJacobianWrtCartesian(positionAngle, dYdC);
final RealMatrix Jac = MatrixUtils.createRealMatrix(dYdC);
// Orbital initial covariance matrix
final RealMatrix initialP = Jac.multiply(cartesianP.multiply(Jac.transpose()));
// Process noise matrix
final RealMatrix cartesianQ = MatrixUtils.createRealDiagonalMatrix(new double[] { 1.e-4, 1.e-4, 1.e-4, 1.e-10, 1.e-10, 1.e-10 });
final RealMatrix Q = Jac.multiply(cartesianQ.multiply(Jac.transpose()));
// Build the Kalman filter
final KalmanEstimatorBuilder kalmanBuilder = new KalmanEstimatorBuilder();
kalmanBuilder.builder(propagatorBuilder);
kalmanBuilder.estimatedMeasurementsParameters(new ParameterDriversList());
kalmanBuilder.initialCovarianceMatrix(initialP);
kalmanBuilder.processNoiseMatrixProvider(new ConstantProcessNoise(Q));
final KalmanEstimator kalman = kalmanBuilder.build();
// Filter the measurements and check the results
final double expectedDeltaPos = 0.;
final double posEps = 2.91e-2;
final double expectedDeltaVel = 0.;
final double velEps = 5.52e-6;
final double[] expectedSigmasPos = { 1.747570, 0.666879, 1.696182 };
final double sigmaPosEps = 1e-6;
final double[] expectedSigmasVel = { 5.413666e-4, 4.088359e-4, 4.315316e-4 };
final double sigmaVelEps = 1e-10;
EstimationTestUtils.checkKalmanFit(context, kalman, measurements, refOrbit, positionAngle, expectedDeltaPos, posEps, expectedDeltaVel, velEps, expectedSigmasPos, sigmaPosEps, expectedSigmasVel, sigmaVelEps);
}
use of org.hipparchus.linear.RealMatrix in project Orekit by CS-SI.
the class KalmanEstimatorTest method testKeplerianRangeWithOnBoardAntennaOffset.
/**
* Perfect range measurements with a biased start and an on-board antenna range offset
* Keplerian formalism
* @throws OrekitException
*/
@Test
public void testKeplerianRangeWithOnBoardAntennaOffset() throws OrekitException {
// Create context
Context context = EstimationTestUtils.eccentricContext("regular-data:potential:tides");
// Create initial orbit and propagator builder
final OrbitType orbitType = OrbitType.KEPLERIAN;
final PositionAngle positionAngle = PositionAngle.TRUE;
final boolean perfectStart = true;
final double minStep = 1.e-6;
final double maxStep = 60.;
final double dP = 1.;
final NumericalPropagatorBuilder propagatorBuilder = context.createBuilder(orbitType, positionAngle, perfectStart, minStep, maxStep, dP);
propagatorBuilder.setAttitudeProvider(new LofOffset(propagatorBuilder.getFrame(), LOFType.LVLH));
// Antenna phase center definition
final Vector3D antennaPhaseCenter = new Vector3D(-1.2, 2.3, -0.7);
// Create perfect range measurements with antenna offset
final Propagator propagator = EstimationTestUtils.createPropagator(context.initialOrbit, propagatorBuilder);
final List<ObservedMeasurement<?>> measurements = EstimationTestUtils.createMeasurements(propagator, new RangeMeasurementCreator(context, antennaPhaseCenter), 1.0, 3.0, 300.0);
// Add antenna offset to the measurements
final OnBoardAntennaRangeModifier obaModifier = new OnBoardAntennaRangeModifier(antennaPhaseCenter);
for (final ObservedMeasurement<?> range : measurements) {
((Range) range).addModifier(obaModifier);
}
// Reference propagator for estimation performances
final NumericalPropagator referencePropagator = propagatorBuilder.buildPropagator(propagatorBuilder.getSelectedNormalizedParameters());
// Reference position/velocity at last measurement date
final Orbit refOrbit = referencePropagator.propagate(measurements.get(measurements.size() - 1).getDate()).getOrbit();
// Change semi-major axis of 1.2m as in the batch test
ParameterDriver aDriver = propagatorBuilder.getOrbitalParametersDrivers().getDrivers().get(0);
aDriver.setValue(aDriver.getValue() + 1.2);
aDriver.setReferenceDate(AbsoluteDate.GALILEO_EPOCH);
// Cartesian covariance matrix initialization
// 100m on position / 1e-2m/s on velocity
final RealMatrix cartesianP = MatrixUtils.createRealDiagonalMatrix(new double[] { 10., 10., 10., 1e-3, 1e-3, 1e-3 });
// Jacobian of the orbital parameters w/r to Cartesian
final Orbit initialOrbit = OrbitType.KEPLERIAN.convertType(context.initialOrbit);
final double[][] dYdC = new double[6][6];
initialOrbit.getJacobianWrtCartesian(PositionAngle.TRUE, dYdC);
final RealMatrix Jac = MatrixUtils.createRealMatrix(dYdC);
// Keplerian initial covariance matrix
final RealMatrix initialP = Jac.multiply(cartesianP.multiply(Jac.transpose()));
// Process noise matrix is set to 0 here
RealMatrix Q = MatrixUtils.createRealMatrix(6, 6);
// Build the Kalman filter
final KalmanEstimatorBuilder kalmanBuilder = new KalmanEstimatorBuilder();
kalmanBuilder.builder(propagatorBuilder);
kalmanBuilder.estimatedMeasurementsParameters(new ParameterDriversList());
kalmanBuilder.initialCovarianceMatrix(initialP);
kalmanBuilder.processNoiseMatrixProvider(new ConstantProcessNoise(Q));
final KalmanEstimator kalman = kalmanBuilder.build();
// Filter the measurements and check the results
final double expectedDeltaPos = 0.;
final double posEps = 4.57e-3;
final double expectedDeltaVel = 0.;
final double velEps = 7.29e-6;
final double[] expectedSigmasPos = { 1.105194, 0.930785, 1.254579 };
final double sigmaPosEps = 1e-6;
final double[] expectedSigmasVel = { 6.193718e-4, 4.088774e-4, 3.299135e-4 };
final double sigmaVelEps = 1e-10;
EstimationTestUtils.checkKalmanFit(context, kalman, measurements, refOrbit, positionAngle, expectedDeltaPos, posEps, expectedDeltaVel, velEps, expectedSigmasPos, sigmaPosEps, expectedSigmasVel, sigmaVelEps);
}
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