Java tutorial
/* Copyright 2002-2015 CS Systmes d'Information * Licensed to CS Systmes d'Information (CS) under one or more * contributor license agreements. See the NOTICE file distributed with * this work for additional information regarding copyright ownership. * CS licenses this file to You under the Apache License, Version 2.0 * (the "License"); you may not use this file except in compliance with * the License. You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ package org.orekit.utils; import java.util.ArrayList; import java.util.List; import java.util.Random; import org.apache.commons.math3.analysis.differentiation.DerivativeStructure; import org.apache.commons.math3.analysis.polynomials.PolynomialFunction; import org.apache.commons.math3.geometry.euclidean.threed.FieldVector3D; import org.apache.commons.math3.geometry.euclidean.threed.Vector3D; import org.apache.commons.math3.util.FastMath; import org.junit.Assert; import org.junit.Test; import org.orekit.Utils; import org.orekit.errors.OrekitException; import org.orekit.time.AbsoluteDate; public class TimeStampedPVCoordinatesTest { @Test public void testPVOnlyConstructor() { //setup AbsoluteDate date = AbsoluteDate.J2000_EPOCH; Vector3D p = new Vector3D(1, 2, 3); Vector3D v = new Vector3D(4, 5, 6); //action TimeStampedPVCoordinates actual = new TimeStampedPVCoordinates(date, p, v); //verify Assert.assertEquals(date, actual.getDate()); Assert.assertEquals(1, actual.getPosition().getX(), 0); Assert.assertEquals(2, actual.getPosition().getY(), 0); Assert.assertEquals(3, actual.getPosition().getZ(), 0); Assert.assertEquals(4, actual.getVelocity().getX(), 0); Assert.assertEquals(5, actual.getVelocity().getY(), 0); Assert.assertEquals(6, actual.getVelocity().getZ(), 0); Assert.assertEquals(Vector3D.ZERO, actual.getAcceleration()); } @Test public void testPVCoordinatesCopyConstructor() { //setup AbsoluteDate date = AbsoluteDate.J2000_EPOCH; PVCoordinates pv = new PVCoordinates(new Vector3D(1, 2, 3), new Vector3D(4, 5, 6)); //action TimeStampedPVCoordinates actual = new TimeStampedPVCoordinates(date, pv); //verify Assert.assertEquals(date, actual.getDate()); Assert.assertEquals(1, actual.getPosition().getX(), 0); Assert.assertEquals(2, actual.getPosition().getY(), 0); Assert.assertEquals(3, actual.getPosition().getZ(), 0); Assert.assertEquals(4, actual.getVelocity().getX(), 0); Assert.assertEquals(5, actual.getVelocity().getY(), 0); Assert.assertEquals(6, actual.getVelocity().getZ(), 0); Assert.assertEquals(Vector3D.ZERO, actual.getAcceleration()); } @Test public void testLinearConstructors() { TimeStampedPVCoordinates pv1 = new TimeStampedPVCoordinates(AbsoluteDate.CCSDS_EPOCH, new Vector3D(1, 0.1, 10), new Vector3D(-1, -0.1, -10), new Vector3D(10, -1.0, -100)); TimeStampedPVCoordinates pv2 = new TimeStampedPVCoordinates(AbsoluteDate.FIFTIES_EPOCH, new Vector3D(2, 0.2, 20), new Vector3D(-2, -0.2, -20), new Vector3D(20, -2.0, -200)); TimeStampedPVCoordinates pv3 = new TimeStampedPVCoordinates(AbsoluteDate.GALILEO_EPOCH, new Vector3D(3, 0.3, 30), new Vector3D(-3, -0.3, -30), new Vector3D(30, -3.0, -300)); TimeStampedPVCoordinates pv4 = new TimeStampedPVCoordinates(AbsoluteDate.JULIAN_EPOCH, new Vector3D(4, 0.4, 40), new Vector3D(-4, -0.4, -40), new Vector3D(40, -4.0, -400)); checkPV(pv4, new TimeStampedPVCoordinates(AbsoluteDate.JULIAN_EPOCH, 4, pv1), 1.0e-15); checkPV(pv2, new TimeStampedPVCoordinates(AbsoluteDate.FIFTIES_EPOCH, pv1, pv3), 1.0e-15); checkPV(pv3, new TimeStampedPVCoordinates(AbsoluteDate.GALILEO_EPOCH, 1, pv1, 1, pv2), 1.0e-15); checkPV(new TimeStampedPVCoordinates(AbsoluteDate.J2000_EPOCH, 2, pv4), new TimeStampedPVCoordinates(AbsoluteDate.J2000_EPOCH, 3, pv1, 1, pv2, 1, pv3), 1.0e-15); checkPV(new TimeStampedPVCoordinates(AbsoluteDate.J2000_EPOCH, 3, pv3), new TimeStampedPVCoordinates(AbsoluteDate.J2000_EPOCH, 3, pv1, 1, pv2, 1, pv4), 1.0e-15); checkPV(new TimeStampedPVCoordinates(AbsoluteDate.J2000_EPOCH, 5, pv4), new TimeStampedPVCoordinates(AbsoluteDate.J2000_EPOCH, 4, pv1, 3, pv2, 2, pv3, 1, pv4), 1.0e-15); } @Test public void testToDerivativeStructureVector2() throws OrekitException { FieldVector3D<DerivativeStructure> fv = new TimeStampedPVCoordinates(AbsoluteDate.GALILEO_EPOCH, new Vector3D(1, 0.1, 10), new Vector3D(-1, -0.1, -10), new Vector3D(10, -1.0, -100)) .toDerivativeStructureVector(2); Assert.assertEquals(1, fv.getX().getFreeParameters()); Assert.assertEquals(2, fv.getX().getOrder()); Assert.assertEquals(1.0, fv.getX().getReal(), 1.0e-10); Assert.assertEquals(0.1, fv.getY().getReal(), 1.0e-10); Assert.assertEquals(10.0, fv.getZ().getReal(), 1.0e-10); Assert.assertEquals(-1.0, fv.getX().getPartialDerivative(1), 1.0e-15); Assert.assertEquals(-0.1, fv.getY().getPartialDerivative(1), 1.0e-15); Assert.assertEquals(-10.0, fv.getZ().getPartialDerivative(1), 1.0e-15); Assert.assertEquals(10.0, fv.getX().getPartialDerivative(2), 1.0e-15); Assert.assertEquals(-1.0, fv.getY().getPartialDerivative(2), 1.0e-15); Assert.assertEquals(-100.0, fv.getZ().getPartialDerivative(2), 1.0e-15); checkPV(new TimeStampedPVCoordinates(AbsoluteDate.GALILEO_EPOCH, new Vector3D(1, 0.1, 10), new Vector3D(-1, -0.1, -10), new Vector3D(10, -1.0, -100)), new TimeStampedPVCoordinates(AbsoluteDate.GALILEO_EPOCH, fv), 1.0e-15); for (double dt = 0; dt < 10; dt += 0.125) { Vector3D p = new PVCoordinates(new Vector3D(1, 0.1, 10), new Vector3D(-1, -0.1, -10), new Vector3D(10, -1.0, -100)).shiftedBy(dt).getPosition(); Assert.assertEquals(p.getX(), fv.getX().taylor(dt), 1.0e-14); Assert.assertEquals(p.getY(), fv.getY().taylor(dt), 1.0e-14); Assert.assertEquals(p.getZ(), fv.getZ().taylor(dt), 1.0e-14); } } @Test public void testShift() { Vector3D p1 = new Vector3D(1, 0.1, 10); Vector3D v1 = new Vector3D(-1, -0.1, -10); Vector3D a1 = new Vector3D(10, 1.0, 100); Vector3D p2 = new Vector3D(7, 0.7, 70); Vector3D v2 = new Vector3D(-11, -1.1, -110); Vector3D a2 = new Vector3D(10, 1.0, 100); checkPV(new TimeStampedPVCoordinates(AbsoluteDate.J2000_EPOCH, p2, v2, a2), new TimeStampedPVCoordinates(AbsoluteDate.J2000_EPOCH.shiftedBy(1.0), p1, v1, a1).shiftedBy(-1.0), 1.0e-15); Assert.assertEquals(0.0, TimeStampedPVCoordinates.estimateVelocity(p1, p2, -1.0) .subtract(new Vector3D(-6, -0.6, -60)).getNorm(), 1.0e-15); } @Test public void testToString() { Utils.setDataRoot("regular-data"); TimeStampedPVCoordinates pv = new TimeStampedPVCoordinates(AbsoluteDate.J2000_EPOCH, new Vector3D(1, 0.1, 10), new Vector3D(-1, -0.1, -10), new Vector3D(10, 1.0, 100)); Assert.assertEquals( "{2000-01-01T11:58:55.816, P(1.0, 0.1, 10.0), V(-1.0, -0.1, -10.0), A(10.0, 1.0, 100.0)}", pv.toString()); } @Test public void testInterpolatePolynomialPVA() { Random random = new Random(0xfe3945fcb8bf47cel); AbsoluteDate t0 = AbsoluteDate.J2000_EPOCH; for (int i = 0; i < 20; ++i) { PolynomialFunction px = randomPolynomial(5, random); PolynomialFunction py = randomPolynomial(5, random); PolynomialFunction pz = randomPolynomial(5, random); PolynomialFunction pxDot = px.polynomialDerivative(); PolynomialFunction pyDot = py.polynomialDerivative(); PolynomialFunction pzDot = pz.polynomialDerivative(); PolynomialFunction pxDotDot = pxDot.polynomialDerivative(); PolynomialFunction pyDotDot = pyDot.polynomialDerivative(); PolynomialFunction pzDotDot = pzDot.polynomialDerivative(); List<TimeStampedPVCoordinates> sample = new ArrayList<TimeStampedPVCoordinates>(); for (double dt : new double[] { 0.0, 0.5, 1.0 }) { Vector3D position = new Vector3D(px.value(dt), py.value(dt), pz.value(dt)); Vector3D velocity = new Vector3D(pxDot.value(dt), pyDot.value(dt), pzDot.value(dt)); Vector3D acceleration = new Vector3D(pxDotDot.value(dt), pyDotDot.value(dt), pzDotDot.value(dt)); sample.add(new TimeStampedPVCoordinates(t0.shiftedBy(dt), position, velocity, acceleration)); } for (double dt = 0; dt < 1.0; dt += 0.01) { TimeStampedPVCoordinates interpolated = TimeStampedPVCoordinates.interpolate(t0.shiftedBy(dt), CartesianDerivativesFilter.USE_PVA, sample); Vector3D p = interpolated.getPosition(); Vector3D v = interpolated.getVelocity(); Vector3D a = interpolated.getAcceleration(); Assert.assertEquals(px.value(dt), p.getX(), 4.0e-16 * p.getNorm()); Assert.assertEquals(py.value(dt), p.getY(), 4.0e-16 * p.getNorm()); Assert.assertEquals(pz.value(dt), p.getZ(), 4.0e-16 * p.getNorm()); Assert.assertEquals(pxDot.value(dt), v.getX(), 9.0e-16 * v.getNorm()); Assert.assertEquals(pyDot.value(dt), v.getY(), 9.0e-16 * v.getNorm()); Assert.assertEquals(pzDot.value(dt), v.getZ(), 9.0e-16 * v.getNorm()); Assert.assertEquals(pxDotDot.value(dt), a.getX(), 9.0e-15 * a.getNorm()); Assert.assertEquals(pyDotDot.value(dt), a.getY(), 9.0e-15 * a.getNorm()); Assert.assertEquals(pzDotDot.value(dt), a.getZ(), 9.0e-15 * a.getNorm()); } } } @Test public void testInterpolatePolynomialPV() { Random random = new Random(0xae7771c9933407bdl); AbsoluteDate t0 = AbsoluteDate.J2000_EPOCH; for (int i = 0; i < 20; ++i) { PolynomialFunction px = randomPolynomial(5, random); PolynomialFunction py = randomPolynomial(5, random); PolynomialFunction pz = randomPolynomial(5, random); PolynomialFunction pxDot = px.polynomialDerivative(); PolynomialFunction pyDot = py.polynomialDerivative(); PolynomialFunction pzDot = pz.polynomialDerivative(); PolynomialFunction pxDotDot = pxDot.polynomialDerivative(); PolynomialFunction pyDotDot = pyDot.polynomialDerivative(); PolynomialFunction pzDotDot = pzDot.polynomialDerivative(); List<TimeStampedPVCoordinates> sample = new ArrayList<TimeStampedPVCoordinates>(); for (double dt : new double[] { 0.0, 0.5, 1.0 }) { Vector3D position = new Vector3D(px.value(dt), py.value(dt), pz.value(dt)); Vector3D velocity = new Vector3D(pxDot.value(dt), pyDot.value(dt), pzDot.value(dt)); sample.add(new TimeStampedPVCoordinates(t0.shiftedBy(dt), position, velocity, Vector3D.ZERO)); } for (double dt = 0; dt < 1.0; dt += 0.01) { TimeStampedPVCoordinates interpolated = TimeStampedPVCoordinates.interpolate(t0.shiftedBy(dt), CartesianDerivativesFilter.USE_PV, sample); Vector3D p = interpolated.getPosition(); Vector3D v = interpolated.getVelocity(); Vector3D a = interpolated.getAcceleration(); Assert.assertEquals(px.value(dt), p.getX(), 4.0e-16 * p.getNorm()); Assert.assertEquals(py.value(dt), p.getY(), 4.0e-16 * p.getNorm()); Assert.assertEquals(pz.value(dt), p.getZ(), 4.0e-16 * p.getNorm()); Assert.assertEquals(pxDot.value(dt), v.getX(), 9.0e-16 * v.getNorm()); Assert.assertEquals(pyDot.value(dt), v.getY(), 9.0e-16 * v.getNorm()); Assert.assertEquals(pzDot.value(dt), v.getZ(), 9.0e-16 * v.getNorm()); Assert.assertEquals(pxDotDot.value(dt), a.getX(), 1.0e-14 * a.getNorm()); Assert.assertEquals(pyDotDot.value(dt), a.getY(), 1.0e-14 * a.getNorm()); Assert.assertEquals(pzDotDot.value(dt), a.getZ(), 1.0e-14 * a.getNorm()); } } } @Test public void testInterpolatePolynomialPositionOnly() { Random random = new Random(0x88740a12e4299003l); AbsoluteDate t0 = AbsoluteDate.J2000_EPOCH; for (int i = 0; i < 20; ++i) { PolynomialFunction px = randomPolynomial(5, random); PolynomialFunction py = randomPolynomial(5, random); PolynomialFunction pz = randomPolynomial(5, random); PolynomialFunction pxDot = px.polynomialDerivative(); PolynomialFunction pyDot = py.polynomialDerivative(); PolynomialFunction pzDot = pz.polynomialDerivative(); PolynomialFunction pxDotDot = pxDot.polynomialDerivative(); PolynomialFunction pyDotDot = pyDot.polynomialDerivative(); PolynomialFunction pzDotDot = pzDot.polynomialDerivative(); List<TimeStampedPVCoordinates> sample = new ArrayList<TimeStampedPVCoordinates>(); for (double dt : new double[] { 0.0, 0.2, 0.4, 0.6, 0.8, 1.0 }) { Vector3D position = new Vector3D(px.value(dt), py.value(dt), pz.value(dt)); sample.add(new TimeStampedPVCoordinates(t0.shiftedBy(dt), position, Vector3D.ZERO, Vector3D.ZERO)); } for (double dt = 0; dt < 1.0; dt += 0.01) { TimeStampedPVCoordinates interpolated = TimeStampedPVCoordinates.interpolate(t0.shiftedBy(dt), CartesianDerivativesFilter.USE_P, sample); Vector3D p = interpolated.getPosition(); Vector3D v = interpolated.getVelocity(); Vector3D a = interpolated.getAcceleration(); Assert.assertEquals(px.value(dt), p.getX(), 5.0e-16 * p.getNorm()); Assert.assertEquals(py.value(dt), p.getY(), 5.0e-16 * p.getNorm()); Assert.assertEquals(pz.value(dt), p.getZ(), 5.0e-16 * p.getNorm()); Assert.assertEquals(pxDot.value(dt), v.getX(), 7.0e-15 * v.getNorm()); Assert.assertEquals(pyDot.value(dt), v.getY(), 7.0e-15 * v.getNorm()); Assert.assertEquals(pzDot.value(dt), v.getZ(), 7.0e-15 * v.getNorm()); Assert.assertEquals(pxDotDot.value(dt), a.getX(), 2.0e-13 * a.getNorm()); Assert.assertEquals(pyDotDot.value(dt), a.getY(), 2.0e-13 * a.getNorm()); Assert.assertEquals(pzDotDot.value(dt), a.getZ(), 2.0e-13 * a.getNorm()); } } } @Test public void testInterpolateNonPolynomial() { AbsoluteDate t0 = AbsoluteDate.J2000_EPOCH; List<TimeStampedPVCoordinates> sample = new ArrayList<TimeStampedPVCoordinates>(); for (double dt : new double[] { 0.0, 0.5, 1.0 }) { Vector3D position = new Vector3D(FastMath.cos(dt), FastMath.sin(dt), 0.0); Vector3D velocity = new Vector3D(-FastMath.sin(dt), FastMath.cos(dt), 0.0); Vector3D acceleration = new Vector3D(-FastMath.cos(dt), -FastMath.sin(dt), 0.0); sample.add(new TimeStampedPVCoordinates(t0.shiftedBy(dt), position, velocity, acceleration)); } for (double dt = 0; dt < 1.0; dt += 0.01) { TimeStampedPVCoordinates interpolated = TimeStampedPVCoordinates.interpolate(t0.shiftedBy(dt), CartesianDerivativesFilter.USE_PVA, sample); Vector3D p = interpolated.getPosition(); Vector3D v = interpolated.getVelocity(); Vector3D a = interpolated.getAcceleration(); Assert.assertEquals(FastMath.cos(dt), p.getX(), 3.0e-10 * p.getNorm()); Assert.assertEquals(FastMath.sin(dt), p.getY(), 3.0e-10 * p.getNorm()); Assert.assertEquals(0, p.getZ(), 3.0e-10 * p.getNorm()); Assert.assertEquals(-FastMath.sin(dt), v.getX(), 3.0e-9 * v.getNorm()); Assert.assertEquals(FastMath.cos(dt), v.getY(), 3.0e-9 * v.getNorm()); Assert.assertEquals(0, v.getZ(), 3.0e-9 * v.getNorm()); Assert.assertEquals(-FastMath.cos(dt), a.getX(), 4.0e-8 * a.getNorm()); Assert.assertEquals(-FastMath.sin(dt), a.getY(), 4.0e-8 * a.getNorm()); Assert.assertEquals(0, a.getZ(), 4.0e-8 * a.getNorm()); } } private PolynomialFunction randomPolynomial(int degree, Random random) { double[] coeff = new double[1 + degree]; for (int j = 0; j < degree; ++j) { coeff[j] = random.nextDouble(); } return new PolynomialFunction(coeff); } private void checkPV(TimeStampedPVCoordinates expected, TimeStampedPVCoordinates real, double epsilon) { Assert.assertEquals(expected.getDate(), real.getDate()); Assert.assertEquals(expected.getPosition().getX(), real.getPosition().getX(), epsilon); Assert.assertEquals(expected.getPosition().getY(), real.getPosition().getY(), epsilon); Assert.assertEquals(expected.getPosition().getZ(), real.getPosition().getZ(), epsilon); Assert.assertEquals(expected.getVelocity().getX(), real.getVelocity().getX(), epsilon); Assert.assertEquals(expected.getVelocity().getY(), real.getVelocity().getY(), epsilon); Assert.assertEquals(expected.getVelocity().getZ(), real.getVelocity().getZ(), epsilon); Assert.assertEquals(expected.getAcceleration().getX(), real.getAcceleration().getX(), epsilon); Assert.assertEquals(expected.getAcceleration().getY(), real.getAcceleration().getY(), epsilon); Assert.assertEquals(expected.getAcceleration().getZ(), real.getAcceleration().getZ(), epsilon); } }