/* Copyright 2002-2017 CS Systèmes d'Information * Licensed to CS Systèmes 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.frames; import java.lang.reflect.Array; import java.util.ArrayList; import java.util.List; import org.hipparchus.Field; import org.hipparchus.RealFieldElement; import org.hipparchus.geometry.euclidean.threed.FieldLine; import org.hipparchus.geometry.euclidean.threed.FieldRotation; import org.hipparchus.geometry.euclidean.threed.FieldVector3D; import org.hipparchus.geometry.euclidean.threed.Line; import org.hipparchus.geometry.euclidean.threed.RotationConvention; import org.hipparchus.geometry.euclidean.threed.Vector3D; import org.hipparchus.linear.FieldMatrix; import org.hipparchus.linear.MatrixUtils; import org.hipparchus.random.RandomGenerator; import org.hipparchus.random.Well19937a; import org.hipparchus.util.Decimal64Field; import org.hipparchus.util.FastMath; import org.hipparchus.util.MathArrays; import org.junit.Assert; import org.junit.Test; import org.orekit.errors.OrekitException; import org.orekit.time.FieldAbsoluteDate; import org.orekit.utils.CartesianDerivativesFilter; import org.orekit.utils.Constants; import org.orekit.utils.FieldPVCoordinates; import org.orekit.utils.PVCoordinates; import org.orekit.utils.TimeStampedFieldPVCoordinates; public class FieldTransformTest { @Test public void testIdentityTranslation() { doTestIdentityTranslation(Decimal64Field.getInstance()); } private <T extends RealFieldElement<T>> void doTestIdentityTranslation(Field<T> field) { checkNoTransform(FieldTransform.getIdentity(field).shiftedBy(12345.0), new Well19937a(0xfd118eac6b5ec136l)); } @Test public void testIdentityRotation() { doTestIdentityRotation(Decimal64Field.getInstance()); } private <T extends RealFieldElement<T>> void doTestIdentityRotation(Field<T> field) { checkNoTransform(FieldTransform.getIdentity(field), new Well19937a(0xfd118eac6b5ec136l)); } @Test public void testIdentityLine() { doTestIdentityLine(Decimal64Field.getInstance()); } private <T extends RealFieldElement<T>> void doTestIdentityLine(Field<T> field) { RandomGenerator random = new Well19937a(0x98603025df70db7cl); FieldVector3D<T> p1 = randomVector(field, 100.0, random); FieldVector3D<T> p2 = randomVector(field, 100.0, random); FieldLine<T> line = new FieldLine<>(p1, p2, 1.0e-6); FieldLine<T> transformed = FieldTransform.getIdentity(field).transformLine(line); Assert.assertSame(line, transformed); } @Test public void testSimpleComposition() { doTestSimpleComposition(Decimal64Field.getInstance()); } private <T extends RealFieldElement<T>> void doTestSimpleComposition(Field<T> field) { FieldTransform<T> transform = new FieldTransform<>(FieldAbsoluteDate.getJ2000Epoch(field), new FieldTransform<>(FieldAbsoluteDate.getJ2000Epoch(field), new FieldRotation<>(FieldVector3D.getPlusK(field), field.getZero().add(0.5 * FastMath.PI), RotationConvention.VECTOR_OPERATOR)), new FieldTransform<>(FieldAbsoluteDate.getJ2000Epoch(field), FieldVector3D.getPlusI(field))); FieldVector3D<T> u = transform.transformPosition(createVector(field, 1.0, 1.0, 1.0)); FieldVector3D<T> v = createVector(field, 0.0, 1.0, 1.0); Assert.assertEquals(0, u.subtract(v).getNorm().getReal(), 1.0e-15); } @Test public void testAcceleration() { doTestAcceleration(Decimal64Field.getInstance()); } private <T extends RealFieldElement<T>> void doTestAcceleration(Field<T> field) { FieldPVCoordinates<T> initPV = new FieldPVCoordinates<>(createVector(field, 9, 8, 7), createVector(field, 6, 5, 4), createVector(field, 3, 2, 1)); for (double dt = 0; dt < 1; dt += 0.01) { FieldPVCoordinates<T> basePV = initPV.shiftedBy(dt); FieldPVCoordinates<T> transformedPV = evolvingTransform(FieldAbsoluteDate.getJ2000Epoch(field), dt).transformPVCoordinates(basePV); // rebuild transformed acceleration, relying only on transformed position and velocity List<TimeStampedFieldPVCoordinates<T>> sample = new ArrayList<TimeStampedFieldPVCoordinates<T>>(); double h = 1.0e-2; for (int i = -3; i < 4; ++i) { FieldTransform<T> t = evolvingTransform(FieldAbsoluteDate.getJ2000Epoch(field), dt + i * h); FieldPVCoordinates<T> pv = t.transformPVCoordinates(initPV.shiftedBy(dt + i * h)); sample.add(new TimeStampedFieldPVCoordinates<>(t.getDate(), pv.getPosition(), pv.getVelocity(), FieldVector3D.getZero(field))); } FieldPVCoordinates<T> rebuiltPV = TimeStampedFieldPVCoordinates.interpolate(FieldAbsoluteDate.getJ2000Epoch(field).shiftedBy(dt), CartesianDerivativesFilter.USE_PV, sample); checkVector(rebuiltPV.getPosition(), transformedPV.getPosition(), 3.0e-15); checkVector(rebuiltPV.getVelocity(), transformedPV.getVelocity(), 2.0e-15); checkVector(rebuiltPV.getAcceleration(), transformedPV.getAcceleration(), 5.0e-10); } } @Test public void testAccelerationComposition() { doTestAccelerationComposition(Decimal64Field.getInstance()); } private <T extends RealFieldElement<T>> void doTestAccelerationComposition(Field<T> field) { RandomGenerator random = new Well19937a(0x41fdd07d6c9e9f65l); FieldVector3D<T> p1 = randomVector(field, 1.0e3, random); FieldVector3D<T> v1 = randomVector(field, 1.0, random); FieldVector3D<T> a1 = randomVector(field, 1.0e-3, random); FieldRotation<T> r1 = randomRotation(field, random); FieldVector3D<T> o1 = randomVector(field, 0.1, random); FieldVector3D<T> p2 = randomVector(field, 1.0e3, random); FieldVector3D<T> v2 = randomVector(field, 1.0, random); FieldVector3D<T> a2 = randomVector(field, 1.0e-3, random); FieldRotation<T> r2 = randomRotation(field, random); FieldVector3D<T> o2 = randomVector(field, 0.1, random); FieldTransform<T> t1 = new FieldTransform<>(FieldAbsoluteDate.getJ2000Epoch(field), new FieldTransform<>(FieldAbsoluteDate.getJ2000Epoch(field), p1, v1, a1), new FieldTransform<>(FieldAbsoluteDate.getJ2000Epoch(field), r1, o1)); FieldTransform<T> t2 = new FieldTransform<>(FieldAbsoluteDate.getJ2000Epoch(field), new FieldTransform<>(FieldAbsoluteDate.getJ2000Epoch(field), p2, v2, a2), new FieldTransform<>(FieldAbsoluteDate.getJ2000Epoch(field), r2, o2)); FieldTransform<T> t12 = new FieldTransform<>(FieldAbsoluteDate.getJ2000Epoch(field), t1, t2); FieldVector3D<T> q = randomVector(field, 1.0e3, random); FieldVector3D<T> qDot = randomVector(field, 1.0, random); FieldVector3D<T> qDotDot = randomVector(field, 1.0e-3, random); FieldPVCoordinates<T> pva0 = new FieldPVCoordinates<>(q, qDot, qDotDot); FieldPVCoordinates<T> pva1 = t1.transformPVCoordinates(pva0); FieldPVCoordinates<T> pva2 = t2.transformPVCoordinates(pva1); FieldPVCoordinates<T> pvac = t12.transformPVCoordinates(pva0); checkVector(pva2.getPosition(), pvac.getPosition(), 1.0e-15); checkVector(pva2.getVelocity(), pvac.getVelocity(), 1.0e-15); checkVector(pva2.getAcceleration(), pvac.getAcceleration(), 1.0e-15); // despite neither raw transforms have angular acceleration, // the combination does have an angular acceleration, // it is due to the cross product Ω₁ ⨯ Ω₂ Assert.assertEquals(0.0, t1.getAngular().getRotationAcceleration().getNorm().getReal(), 1.0e-15); Assert.assertEquals(0.0, t2.getAngular().getRotationAcceleration().getNorm().getReal(), 1.0e-15); Assert.assertTrue(t12.getAngular().getRotationAcceleration().getNorm().getReal() > 0.01); Assert.assertEquals(0.0, t12.freeze().getCartesian().getVelocity().getNorm().getReal(), 1.0e-15); Assert.assertEquals(0.0, t12.freeze().getCartesian().getAcceleration().getNorm().getReal(), 1.0e-15); Assert.assertEquals(0.0, t12.freeze().getAngular().getRotationRate().getNorm().getReal(), 1.0e-15); Assert.assertEquals(0.0, t12.freeze().getAngular().getRotationAcceleration().getNorm().getReal(), 1.0e-15); } @Test public void testRandomComposition() { doTestRandomComposition(Decimal64Field.getInstance()); } private <T extends RealFieldElement<T>> void doTestRandomComposition(Field<T> field) { RandomGenerator random = new Well19937a(0x171c79e323a1123l); for (int i = 0; i < 20; ++i) { // build a complex transform by composing primitive ones int n = random.nextInt(20); @SuppressWarnings("unchecked") FieldTransform<T>[] transforms = (FieldTransform<T>[]) Array.newInstance(FieldTransform.class, n); FieldTransform<T> combined = FieldTransform.getIdentity(field); for (int k = 0; k < n; ++k) { transforms[k] = random.nextBoolean() ? new FieldTransform<>(FieldAbsoluteDate.getJ2000Epoch(field), randomVector(field, 1.0e3, random), randomVector(field, 1.0, random), randomVector(field, 1.0e-3, random)) : new FieldTransform<>(FieldAbsoluteDate.getJ2000Epoch(field), randomRotation(field, random), randomVector(field, 0.01, random), randomVector(field, 1.0e-4, random)); combined = new FieldTransform<>(FieldAbsoluteDate.getJ2000Epoch(field), combined, transforms[k]); } // check the composition for (int j = 0; j < 10; ++j) { FieldVector3D<T> a = randomVector(field, 1.0, random); FieldVector3D<T> b = randomVector(field, 1.0e3, random); FieldPVCoordinates<T> c = new FieldPVCoordinates<>(randomVector(field, 1.0e3, random), randomVector(field, 1.0, random), randomVector(field, 1.0e-3, random)); FieldVector3D<T> aRef = a; FieldVector3D<T> bRef = b; FieldPVCoordinates<T> cRef = c; for (int k = 0; k < n; ++k) { aRef = transforms[k].transformVector(aRef); bRef = transforms[k].transformPosition(bRef); cRef = transforms[k].transformPVCoordinates(cRef); } FieldVector3D<T> aCombined = combined.transformVector(a); FieldVector3D<T> bCombined = combined.transformPosition(b); FieldPVCoordinates<T> cCombined = combined.transformPVCoordinates(c); checkVector(aRef, aCombined, 3.0e-15); checkVector(bRef, bCombined, 5.0e-15); checkVector(cRef.getPosition(), cCombined.getPosition(), 1.0e-14); checkVector(cRef.getVelocity(), cCombined.getVelocity(), 1.0e-14); checkVector(cRef.getAcceleration(), cCombined.getAcceleration(), 1.0e-14); } } } @Test public void testReverse() { doTestReverse(Decimal64Field.getInstance()); } private <T extends RealFieldElement<T>> void doTestReverse(Field<T> field) { RandomGenerator random = new Well19937a(0x9f82ba2b2c98dac5l); for (int i = 0; i < 20; ++i) { FieldTransform<T> combined = randomTransform(field, random); checkNoTransform(new FieldTransform<>(FieldAbsoluteDate.getJ2000Epoch(field), combined, combined.getInverse()), random); } } @Test public void testIdentityJacobianP() { doTestIdentityJacobianP(Decimal64Field.getInstance()); } private <T extends RealFieldElement<T>> void doTestIdentityJacobianP(Field<T> field) { doTestIdentityJacobian(field, 3, CartesianDerivativesFilter.USE_P); } @Test public void testIdentityJacobianPV() { doTestIdentityJacobianPV(Decimal64Field.getInstance()); } private <T extends RealFieldElement<T>> void doTestIdentityJacobianPV(Field<T> field) { doTestIdentityJacobian(field, 6, CartesianDerivativesFilter.USE_PV); } @Test public void testIdentityJacobianPVA() { doTestIdentityJacobianPVA(Decimal64Field.getInstance()); } private <T extends RealFieldElement<T>> void doTestIdentityJacobianPVA(Field<T> field) { doTestIdentityJacobian(field, 9, CartesianDerivativesFilter.USE_PVA); } private <T extends RealFieldElement<T>> void doTestIdentityJacobian(Field<T> field, int n, CartesianDerivativesFilter filter) { T[][] jacobian = MathArrays.buildArray(field, n, n); FieldTransform.getIdentity(field).getJacobian(filter, jacobian); for (int i = 0; i < n; ++i) { for (int j = 0; j < n; ++j) { Assert.assertEquals(i == j ? 1.0 : 0.0, jacobian[i][j].getReal(), 1.0e-15); } } } @Test public void testDecomposeAndRebuild() { doTestDecomposeAndRebuild(Decimal64Field.getInstance()); } private <T extends RealFieldElement<T>> void doTestDecomposeAndRebuild(Field<T> field) { RandomGenerator random = new Well19937a(0xb8ee9da1b05198c9l); for (int i = 0; i < 20; ++i) { FieldTransform<T> combined = randomTransform(field, random); FieldTransform<T> rebuilt = new FieldTransform<>(combined.getFieldDate(), new FieldTransform<>(combined.getFieldDate(), combined.getTranslation(), combined.getVelocity(), combined.getAcceleration()), new FieldTransform<>(combined.getFieldDate(), combined.getRotation(), combined.getRotationRate(), combined.getRotationAcceleration())); checkNoTransform(new FieldTransform<>(FieldAbsoluteDate.getJ2000Epoch(field), combined, rebuilt.getInverse()), random); } } @Test public void testTranslation() { doTestTranslation(Decimal64Field.getInstance()); } private <T extends RealFieldElement<T>> void doTestTranslation(Field<T> field) { RandomGenerator rnd = new Well19937a(0x7e9d737ba4147787l); for (int i = 0; i < 10; ++i) { FieldVector3D<T> delta = randomVector(field, 1.0e3, rnd); FieldTransform<T> transform = new FieldTransform<>(FieldAbsoluteDate.getJ2000Epoch(field), delta); for (int j = 0; j < 10; ++j) { FieldVector3D<T> a = createVector(field, rnd.nextDouble(), rnd.nextDouble(), rnd.nextDouble()); FieldVector3D<T> b = transform.transformVector(a); Assert.assertEquals(0, b.subtract(a).getNorm().getReal(), 1.0e-15); FieldVector3D<T> c = transform.transformPosition(a); Assert.assertEquals(0, c.subtract(a).subtract(delta).getNorm().getReal(), 1.0e-14); } } } @Test public void testTranslationDouble() { doTestTranslationDouble(Decimal64Field.getInstance()); } private <T extends RealFieldElement<T>> void doTestTranslationDouble(Field<T> field) { RandomGenerator rnd = new Well19937a(0x7e9d737ba4147787l); for (int i = 0; i < 10; ++i) { FieldVector3D<T> delta = randomVector(field, 1.0e3, rnd); FieldTransform<T> transform = new FieldTransform<>(FieldAbsoluteDate.getJ2000Epoch(field), delta); for (int j = 0; j < 10; ++j) { Vector3D a = createVector(field, rnd.nextDouble(), rnd.nextDouble(), rnd.nextDouble()).toVector3D(); FieldVector3D<T> b = transform.transformVector(a); Assert.assertEquals(0, b.subtract(a).getNorm().getReal(), 1.0e-15); FieldVector3D<T> c = transform.transformPosition(a); Assert.assertEquals(0, c.subtract(a).subtract(delta).getNorm().getReal(), 1.0e-14); } } } @Test public void testRoughTransPV() { doTestRoughTransPV(Decimal64Field.getInstance()); } private <T extends RealFieldElement<T>> void doTestRoughTransPV(Field<T> field) { FieldPVCoordinates<T> pointP1 = new FieldPVCoordinates<>(FieldVector3D.getPlusI(field), FieldVector3D.getPlusI(field), FieldVector3D.getPlusI(field)); // translation transform test FieldPVCoordinates<T> pointP2 = new FieldPVCoordinates<>(createVector(field, 0, 0, 0), createVector(field, 0, 0, 0)); FieldTransform<T> R1toR2 = new FieldTransform<>(FieldAbsoluteDate.getJ2000Epoch(field), FieldVector3D.getMinusI(field), FieldVector3D.getMinusI(field), FieldVector3D.getMinusI(field)); FieldPVCoordinates<T> result1 = R1toR2.transformPVCoordinates(pointP1); checkVector(pointP2.getPosition(), result1.getPosition(), 1.0e-15); checkVector(pointP2.getVelocity(), result1.getVelocity(), 1.0e-15); checkVector(pointP2.getAcceleration(), result1.getAcceleration(), 1.0e-15); // test inverse translation FieldTransform<T> R2toR1 = R1toR2.getInverse(); FieldPVCoordinates<T> invResult1 = R2toR1.transformPVCoordinates(pointP2); checkVector(pointP1.getPosition(), invResult1.getPosition(), 1.0e-15); checkVector(pointP1.getVelocity(), invResult1.getVelocity(), 1.0e-15); checkVector(pointP1.getAcceleration(), invResult1.getAcceleration(), 1.0e-15); // rotation transform test FieldPVCoordinates<T> pointP3 = new FieldPVCoordinates<>(FieldVector3D.getPlusJ(field), createVector(field, -2, 1, 0), createVector(field, -4, -3, -1)); FieldRotation<T> R = new FieldRotation<>(FieldVector3D.getPlusK(field), field.getZero().add(FastMath.PI / 2), RotationConvention.VECTOR_OPERATOR); FieldTransform<T> R1toR3 = new FieldTransform<>(FieldAbsoluteDate.getJ2000Epoch(field), R, createVector(field, 0, 0, -2), createVector(field, 1, 0, 0)); FieldPVCoordinates<T> result2 = R1toR3.transformPVCoordinates(pointP1); checkVector(pointP3.getPosition(), result2.getPosition(), 1.0e-15); checkVector(pointP3.getVelocity(), result2.getVelocity(), 1.0e-15); checkVector(pointP3.getAcceleration(), result2.getAcceleration(), 1.0e-15); // test inverse rotation FieldTransform<T> R3toR1 = R1toR3.getInverse(); FieldPVCoordinates<T> invResult2 = R3toR1.transformPVCoordinates(pointP3); checkVector(pointP1.getPosition(), invResult2.getPosition(), 1.0e-15); checkVector(pointP1.getVelocity(), invResult2.getVelocity(), 1.0e-15); checkVector(pointP1.getAcceleration(), invResult2.getAcceleration(), 1.0e-15); // combine 2 velocity transform FieldTransform<T> R1toR4 = new FieldTransform<>(FieldAbsoluteDate.getJ2000Epoch(field), createVector(field, -2, 0, 0), createVector(field, -2, 0, 0), createVector(field, -2, 0, 0)); FieldPVCoordinates<T> pointP4 = new FieldPVCoordinates<>(createVector(field, -1, 0, 0), createVector(field, -1, 0, 0), createVector(field, -1, 0, 0)); FieldTransform<T> R2toR4 = new FieldTransform<>(FieldAbsoluteDate.getJ2000Epoch(field), R2toR1, R1toR4); FieldPVCoordinates<T> compResult = R2toR4.transformPVCoordinates(pointP2); checkVector(pointP4.getPosition(), compResult.getPosition(), 1.0e-15); checkVector(pointP4.getVelocity(), compResult.getVelocity(), 1.0e-15); checkVector(pointP4.getAcceleration(), compResult.getAcceleration(), 1.0e-15); // combine 2 rotation tranform FieldPVCoordinates<T> pointP5 = new FieldPVCoordinates<>(createVector(field, -1, 0, 0), createVector(field, -1, 0, 3), createVector(field, 8, 0, 6)); FieldRotation<T> R2 = new FieldRotation<>(createVector(field, 0,0,1), field.getZero().add(FastMath.PI), RotationConvention.VECTOR_OPERATOR); FieldTransform<T> R1toR5 = new FieldTransform<>(FieldAbsoluteDate.getJ2000Epoch(field), R2, createVector(field, 0, -3, 0)); FieldTransform<T> R3toR5 = new FieldTransform<> (FieldAbsoluteDate.getJ2000Epoch(field), R3toR1, R1toR5); FieldPVCoordinates<T> combResult = R3toR5.transformPVCoordinates(pointP3); checkVector(pointP5.getPosition(), combResult.getPosition(), 1.0e-15); checkVector(pointP5.getVelocity(), combResult.getVelocity(), 1.0e-15); checkVector(pointP5.getAcceleration(), combResult.getAcceleration(), 1.0e-15); // combine translation and rotation FieldTransform<T> R2toR3 = new FieldTransform<> (FieldAbsoluteDate.getJ2000Epoch(field), R2toR1,R1toR3); FieldPVCoordinates<T> result = R2toR3.transformPVCoordinates(pointP2); checkVector(pointP3.getPosition(), result.getPosition(), 1.0e-15); checkVector(pointP3.getVelocity(), result.getVelocity(), 1.0e-15); checkVector(pointP3.getAcceleration(), result.getAcceleration(), 1.0e-15); FieldTransform<T> R3toR2 = new FieldTransform<> (FieldAbsoluteDate.getJ2000Epoch(field), R3toR1, R1toR2); result = R3toR2.transformPVCoordinates(pointP3); checkVector(pointP2.getPosition(), result.getPosition(), 1.0e-15); checkVector(pointP2.getVelocity(), result.getVelocity(), 1.0e-15); checkVector(pointP2.getAcceleration(), result.getAcceleration(), 1.0e-15); FieldTransform<T> newR1toR5 = new FieldTransform<>(FieldAbsoluteDate.getJ2000Epoch(field), R1toR2, R2toR3); newR1toR5 = new FieldTransform<>(FieldAbsoluteDate.getJ2000Epoch(field), newR1toR5,R3toR5); result = newR1toR5.transformPVCoordinates(pointP1); checkVector(pointP5.getPosition(), result.getPosition(), 1.0e-15); checkVector(pointP5.getVelocity(), result.getVelocity(), 1.0e-15); checkVector(pointP5.getAcceleration(), result.getAcceleration(), 1.0e-15); // more tests newR1toR5 = new FieldTransform<>(FieldAbsoluteDate.getJ2000Epoch(field), R1toR2, R2toR3); FieldTransform<T> R3toR4 = new FieldTransform<>(FieldAbsoluteDate.getJ2000Epoch(field), R3toR1, R1toR4); newR1toR5 = new FieldTransform<>(FieldAbsoluteDate.getJ2000Epoch(field), newR1toR5, R3toR4); FieldTransform<T> R4toR5 = new FieldTransform<>(FieldAbsoluteDate.getJ2000Epoch(field), R1toR4.getInverse(), R1toR5); newR1toR5 = new FieldTransform<>(FieldAbsoluteDate.getJ2000Epoch(field), newR1toR5, R4toR5); result = newR1toR5.transformPVCoordinates(pointP1); checkVector(pointP5.getPosition(), result.getPosition(), 1.0e-15); checkVector(pointP5.getVelocity(), result.getVelocity(), 1.0e-15); checkVector(pointP5.getAcceleration(), result.getAcceleration(), 1.0e-15); } @Test public void testRotPV() { doTestRotPV(Decimal64Field.getInstance()); } private <T extends RealFieldElement<T>> void doTestRotPV(Field<T> field) { RandomGenerator rnd = new Well19937a(0x73d5554d99427af0l); // Instant Rotation only for (int i = 0; i < 10; ++i) { // Random instant rotation FieldRotation<T> instantRot = randomRotation(field, rnd); FieldVector3D<T> normAxis = instantRot.getAxis(RotationConvention.VECTOR_OPERATOR); T w = instantRot.getAngle().abs().divide(Constants.JULIAN_DAY); // random rotation FieldRotation<T> rot = randomRotation(field, rnd); // so we have a transform FieldTransform<T> tr = new FieldTransform<>(FieldAbsoluteDate.getJ2000Epoch(field), rot, new FieldVector3D<>(w, normAxis)); // random position, velocity, acceleration FieldVector3D<T> pos = randomVector(field, 1.0e3, rnd); FieldVector3D<T> vel = randomVector(field, 1.0, rnd); FieldVector3D<T> acc = randomVector(field, 1.0e-3, rnd); FieldPVCoordinates<T> pvOne = new FieldPVCoordinates<>(pos, vel, acc); // we obtain FieldPVCoordinates<T> pvTwo = tr.transformPVCoordinates(pvOne); // test inverse FieldVector3D<T> resultvel = tr.getInverse().transformPVCoordinates(pvTwo).getVelocity(); checkVector(resultvel, vel, 1.0e-15); } } @Test public void testTransPV() { doTestTransPV(Decimal64Field.getInstance()); } private <T extends RealFieldElement<T>> void doTestTransPV(Field<T> field) { RandomGenerator rnd = new Well19937a(0x73d5554d99427af0l); // translation velocity only : for (int i = 0; i < 10; ++i) { // random position, velocity and acceleration FieldVector3D<T> pos = randomVector(field, 1.0e3, rnd); FieldVector3D<T> vel = randomVector(field, 1.0, rnd); FieldVector3D<T> acc = randomVector(field, 1.0e-3, rnd); FieldPVCoordinates<T> pvOne = new FieldPVCoordinates<>(pos, vel, acc); // random transform FieldVector3D<T> transPos = randomVector(field, 1.0e3, rnd); FieldVector3D<T> transVel = randomVector(field, 1.0, rnd); FieldVector3D<T> transAcc = randomVector(field, 1.0e-3, rnd); FieldTransform<T> tr = new FieldTransform<>(FieldAbsoluteDate.getJ2000Epoch(field), transPos, transVel, transAcc); double dt = 1; // we should obtain FieldVector3D<T> good = tr.transformPosition(pos.add(new FieldVector3D<>(dt, vel))).add(new FieldVector3D<>(dt, transVel)); // we have FieldPVCoordinates<T> pvTwo = tr.transformPVCoordinates(pvOne); FieldVector3D<T> result = pvTwo.getPosition().add(new FieldVector3D<>(dt, pvTwo.getVelocity())); checkVector(good, result, 1.0e-15); // test inverse FieldVector3D<T> resultvel = tr.getInverse(). transformPVCoordinates(pvTwo).getVelocity(); checkVector(resultvel, vel, 1.0e-15); } } @Test public void testTransPVDouble() { doTestTransPVDouble(Decimal64Field.getInstance()); } private <T extends RealFieldElement<T>> void doTestTransPVDouble(Field<T> field) { RandomGenerator rnd = new Well19937a(0x73d5554d99427af0l); // translation velocity only : for (int i = 0; i < 10; ++i) { // random position, velocity and acceleration Vector3D pos = randomVector(field, 1.0e3, rnd).toVector3D(); Vector3D vel = randomVector(field, 1.0, rnd).toVector3D(); Vector3D acc = randomVector(field, 1.0e-3, rnd).toVector3D(); PVCoordinates pvOne = new PVCoordinates(pos, vel, acc); // random transform FieldVector3D<T> transPos = randomVector(field, 1.0e3, rnd); FieldVector3D<T> transVel = randomVector(field, 1.0, rnd); FieldVector3D<T> transAcc = randomVector(field, 1.0e-3, rnd); FieldTransform<T> tr = new FieldTransform<>(FieldAbsoluteDate.getJ2000Epoch(field), transPos, transVel, transAcc); T dt = field.getZero().add(1); // we should obtain FieldVector3D<T> good = tr.transformPosition(new FieldVector3D<>(dt, vel).add(pos)).add(new FieldVector3D<>(dt, transVel)); // we have FieldPVCoordinates<T> pvTwo = tr.transformPVCoordinates(pvOne); FieldVector3D<T> result = pvTwo.getPosition().add(new FieldVector3D<>(dt, pvTwo.getVelocity())); checkVector(good, result, 1.0e-15); // test inverse FieldVector3D<T> resultvel = tr.getInverse(). transformPVCoordinates(pvTwo).getVelocity(); checkVector(resultvel, new FieldVector3D<>(field, vel), 1.0e-15); } } @Test public void testRotation() { doTestRotation(Decimal64Field.getInstance()); } private <T extends RealFieldElement<T>> void doTestRotation(Field<T> field) { RandomGenerator rnd = new Well19937a(0x73d5554d99427af0l); for (int i = 0; i < 10; ++i) { FieldRotation<T> r = randomRotation(field, rnd); FieldVector3D<T> axis = r.getAxis(RotationConvention.VECTOR_OPERATOR); T angle = r.getAngle(); FieldTransform<T> transform = new FieldTransform<>(FieldAbsoluteDate.getJ2000Epoch(field), r); for (int j = 0; j < 10; ++j) { FieldVector3D<T> a = createVector(field, rnd.nextDouble(), rnd.nextDouble(), rnd.nextDouble()); FieldVector3D<T> b = transform.transformVector(a); Assert.assertEquals(FieldVector3D.angle(axis, a).getReal(), FieldVector3D.angle(axis, b).getReal(), 1.0e-14); FieldVector3D<T> aOrtho = FieldVector3D.crossProduct(axis, a); FieldVector3D<T> bOrtho = FieldVector3D.crossProduct(axis, b); Assert.assertEquals(angle.getReal(), FieldVector3D.angle(aOrtho, bOrtho).getReal(), 1.0e-14); FieldVector3D<T> c = transform.transformPosition(a); Assert.assertEquals(0, c.subtract(b).getNorm().getReal(), 1.0e-14); } } } @Test public void testJacobianP() { doTestJacobianP(Decimal64Field.getInstance()); } private <T extends RealFieldElement<T>> void doTestJacobianP(Field<T> field) { // base directions for finite differences @SuppressWarnings("unchecked") FieldPVCoordinates<T>[] directions = (FieldPVCoordinates<T>[]) Array.newInstance(FieldPVCoordinates.class, 3); directions[0] = new FieldPVCoordinates<>(FieldVector3D.getPlusI(field), FieldVector3D.getZero(field), FieldVector3D.getZero(field)); directions[1] = new FieldPVCoordinates<>(FieldVector3D.getPlusJ(field), FieldVector3D.getZero(field), FieldVector3D.getZero(field)); directions[2] = new FieldPVCoordinates<>(FieldVector3D.getPlusK(field), FieldVector3D.getZero(field), FieldVector3D.getZero(field)); double h = 0.01; RandomGenerator random = new Well19937a(0x47fd0d6809f4b173l); for (int i = 0; i < 20; ++i) { // generate a random transform FieldTransform<T> combined = randomTransform(field, random); // compute Jacobian T[][] jacobian = MathArrays.buildArray(field, 9, 9); for (int l = 0; l < jacobian.length; ++l) { for (int c = 0; c < jacobian[l].length; ++c) { jacobian[l][c] = field.getZero().add(l + 0.1 * c); } } combined.getJacobian(CartesianDerivativesFilter.USE_P, jacobian); for (int j = 0; j < 100; ++j) { FieldPVCoordinates<T> pv0 = new FieldPVCoordinates<>(randomVector(field, 1e3, random), randomVector(field, 1.0, random), randomVector(field, 1.0e-3, random)); double epsilonP = 2.0e-12 * pv0.getPosition().getNorm().getReal(); for (int c = 0; c < directions.length; ++c) { // eight points finite differences estimation of a Jacobian column FieldPVCoordinates<T> pvm4h = combined.transformPVCoordinates(new FieldPVCoordinates<>(1.0, pv0, -4 * h, directions[c])); FieldPVCoordinates<T> pvm3h = combined.transformPVCoordinates(new FieldPVCoordinates<>(1.0, pv0, -3 * h, directions[c])); FieldPVCoordinates<T> pvm2h = combined.transformPVCoordinates(new FieldPVCoordinates<>(1.0, pv0, -2 * h, directions[c])); FieldPVCoordinates<T> pvm1h = combined.transformPVCoordinates(new FieldPVCoordinates<>(1.0, pv0, -1 * h, directions[c])); FieldPVCoordinates<T> pvp1h = combined.transformPVCoordinates(new FieldPVCoordinates<>(1.0, pv0, +1 * h, directions[c])); FieldPVCoordinates<T> pvp2h = combined.transformPVCoordinates(new FieldPVCoordinates<>(1.0, pv0, +2 * h, directions[c])); FieldPVCoordinates<T> pvp3h = combined.transformPVCoordinates(new FieldPVCoordinates<>(1.0, pv0, +3 * h, directions[c])); FieldPVCoordinates<T> pvp4h = combined.transformPVCoordinates(new FieldPVCoordinates<>(1.0, pv0, +4 * h, directions[c])); FieldPVCoordinates<T> d4 = new FieldPVCoordinates<>(pvm4h, pvp4h); FieldPVCoordinates<T> d3 = new FieldPVCoordinates<>(pvm3h, pvp3h); FieldPVCoordinates<T> d2 = new FieldPVCoordinates<>(pvm2h, pvp2h); FieldPVCoordinates<T> d1 = new FieldPVCoordinates<>(pvm1h, pvp1h); double d = 1.0 / (840 * h); FieldPVCoordinates<T> estimatedColumn = new FieldPVCoordinates<>(-3 * d, d4, 32 * d, d3, -168 * d, d2, 672 * d, d1); // check analytical Jacobian against finite difference reference Assert.assertEquals(estimatedColumn.getPosition().getX().getReal(), jacobian[0][c].getReal(), epsilonP); Assert.assertEquals(estimatedColumn.getPosition().getY().getReal(), jacobian[1][c].getReal(), epsilonP); Assert.assertEquals(estimatedColumn.getPosition().getZ().getReal(), jacobian[2][c].getReal(), epsilonP); // check the rest of the matrix remains untouched for (int l = 3; l < jacobian.length; ++l) { Assert.assertEquals(l + 0.1 * c, jacobian[l][c].getReal(), 1.0e-15); } } // check the rest of the matrix remains untouched for (int c = directions.length; c < jacobian[0].length; ++c) { for (int l = 0; l < jacobian.length; ++l) { Assert.assertEquals(l + 0.1 * c, jacobian[l][c].getReal(), 1.0e-15); } } } } } @Test public void testJacobianPV() { doTestJacobianPV(Decimal64Field.getInstance()); } private <T extends RealFieldElement<T>> void doTestJacobianPV(Field<T> field) { // base directions for finite differences @SuppressWarnings("unchecked") FieldPVCoordinates<T>[] directions = (FieldPVCoordinates<T>[]) Array.newInstance(FieldPVCoordinates.class, 6); directions[0] = new FieldPVCoordinates<>(FieldVector3D.getPlusI(field), FieldVector3D.getZero(field), FieldVector3D.getZero(field)); directions[1] = new FieldPVCoordinates<>(FieldVector3D.getPlusJ(field), FieldVector3D.getZero(field), FieldVector3D.getZero(field)); directions[2] = new FieldPVCoordinates<>(FieldVector3D.getPlusK(field), FieldVector3D.getZero(field), FieldVector3D.getZero(field)); directions[3] = new FieldPVCoordinates<>(FieldVector3D.getZero(field), FieldVector3D.getPlusI(field), FieldVector3D.getZero(field)); directions[4] = new FieldPVCoordinates<>(FieldVector3D.getZero(field), FieldVector3D.getPlusJ(field), FieldVector3D.getZero(field)); directions[5] = new FieldPVCoordinates<>(FieldVector3D.getZero(field), FieldVector3D.getPlusK(field), FieldVector3D.getZero(field)); double h = 0.01; RandomGenerator random = new Well19937a(0xce2bfddfbb9796bel); for (int i = 0; i < 20; ++i) { // generate a random transform FieldTransform<T> combined = randomTransform(field, random); // compute Jacobian T[][] jacobian = MathArrays.buildArray(field, 9, 9); for (int l = 0; l < jacobian.length; ++l) { for (int c = 0; c < jacobian[l].length; ++c) { jacobian[l][c] = field.getZero().add(l + 0.1 * c); } } combined.getJacobian(CartesianDerivativesFilter.USE_PV, jacobian); for (int j = 0; j < 100; ++j) { FieldPVCoordinates<T> pv0 = new FieldPVCoordinates<>(randomVector(field, 1e3, random), randomVector(field, 1.0, random), randomVector(field, 1.0e-3, random)); double epsilonP = 2.0e-12 * pv0.getPosition().getNorm().getReal(); double epsilonV = 6.0e-11 * pv0.getVelocity().getNorm().getReal(); for (int c = 0; c < directions.length; ++c) { // eight points finite differences estimation of a Jacobian column FieldPVCoordinates<T> pvm4h = combined.transformPVCoordinates(new FieldPVCoordinates<>(1.0, pv0, -4 * h, directions[c])); FieldPVCoordinates<T> pvm3h = combined.transformPVCoordinates(new FieldPVCoordinates<>(1.0, pv0, -3 * h, directions[c])); FieldPVCoordinates<T> pvm2h = combined.transformPVCoordinates(new FieldPVCoordinates<>(1.0, pv0, -2 * h, directions[c])); FieldPVCoordinates<T> pvm1h = combined.transformPVCoordinates(new FieldPVCoordinates<>(1.0, pv0, -1 * h, directions[c])); FieldPVCoordinates<T> pvp1h = combined.transformPVCoordinates(new FieldPVCoordinates<>(1.0, pv0, +1 * h, directions[c])); FieldPVCoordinates<T> pvp2h = combined.transformPVCoordinates(new FieldPVCoordinates<>(1.0, pv0, +2 * h, directions[c])); FieldPVCoordinates<T> pvp3h = combined.transformPVCoordinates(new FieldPVCoordinates<>(1.0, pv0, +3 * h, directions[c])); FieldPVCoordinates<T> pvp4h = combined.transformPVCoordinates(new FieldPVCoordinates<>(1.0, pv0, +4 * h, directions[c])); FieldPVCoordinates<T> d4 = new FieldPVCoordinates<>(pvm4h, pvp4h); FieldPVCoordinates<T> d3 = new FieldPVCoordinates<>(pvm3h, pvp3h); FieldPVCoordinates<T> d2 = new FieldPVCoordinates<>(pvm2h, pvp2h); FieldPVCoordinates<T> d1 = new FieldPVCoordinates<>(pvm1h, pvp1h); double d = 1.0 / (840 * h); FieldPVCoordinates<T> estimatedColumn = new FieldPVCoordinates<>(-3 * d, d4, 32 * d, d3, -168 * d, d2, 672 * d, d1); // check analytical Jacobian against finite difference reference Assert.assertEquals(estimatedColumn.getPosition().getX().getReal(), jacobian[0][c].getReal(), epsilonP); Assert.assertEquals(estimatedColumn.getPosition().getY().getReal(), jacobian[1][c].getReal(), epsilonP); Assert.assertEquals(estimatedColumn.getPosition().getZ().getReal(), jacobian[2][c].getReal(), epsilonP); Assert.assertEquals(estimatedColumn.getVelocity().getX().getReal(), jacobian[3][c].getReal(), epsilonV); Assert.assertEquals(estimatedColumn.getVelocity().getY().getReal(), jacobian[4][c].getReal(), epsilonV); Assert.assertEquals(estimatedColumn.getVelocity().getZ().getReal(), jacobian[5][c].getReal(), epsilonV); // check the rest of the matrix remains untouched for (int l = 6; l < jacobian.length; ++l) { Assert.assertEquals(l + 0.1 * c, jacobian[l][c].getReal(), 1.0e-15); } } // check the rest of the matrix remains untouched for (int c = directions.length; c < jacobian[0].length; ++c) { for (int l = 0; l < jacobian.length; ++l) { Assert.assertEquals(l + 0.1 * c, jacobian[l][c].getReal(), 1.0e-15); } } } } } @Test public void testJacobianPVA() { doTestJacobianPVA(Decimal64Field.getInstance()); } private <T extends RealFieldElement<T>> void doTestJacobianPVA(Field<T> field) { // base directions for finite differences @SuppressWarnings("unchecked") FieldPVCoordinates<T>[] directions = (FieldPVCoordinates<T>[]) Array.newInstance(FieldPVCoordinates.class, 9); directions[0] = new FieldPVCoordinates<>(FieldVector3D.getPlusI(field), FieldVector3D.getZero(field), FieldVector3D.getZero(field)); directions[1] = new FieldPVCoordinates<>(FieldVector3D.getPlusJ(field), FieldVector3D.getZero(field), FieldVector3D.getZero(field)); directions[2] = new FieldPVCoordinates<>(FieldVector3D.getPlusK(field), FieldVector3D.getZero(field), FieldVector3D.getZero(field)); directions[3] = new FieldPVCoordinates<>(FieldVector3D.getZero(field), FieldVector3D.getPlusI(field), FieldVector3D.getZero(field)); directions[4] = new FieldPVCoordinates<>(FieldVector3D.getZero(field), FieldVector3D.getPlusJ(field), FieldVector3D.getZero(field)); directions[5] = new FieldPVCoordinates<>(FieldVector3D.getZero(field), FieldVector3D.getPlusK(field), FieldVector3D.getZero(field)); directions[6] = new FieldPVCoordinates<>(FieldVector3D.getZero(field), FieldVector3D.getZero(field), FieldVector3D.getPlusI(field)); directions[7] = new FieldPVCoordinates<>(FieldVector3D.getZero(field), FieldVector3D.getZero(field), FieldVector3D.getPlusJ(field)); directions[8] = new FieldPVCoordinates<>(FieldVector3D.getZero(field), FieldVector3D.getZero(field), FieldVector3D.getPlusK(field)); double h = 0.01; RandomGenerator random = new Well19937a(0xd223e88b6232198fl); for (int i = 0; i < 20; ++i) { // generate a random transform FieldTransform<T> combined = randomTransform(field, random); // compute Jacobian T[][] jacobian = MathArrays.buildArray(field, 9, 9); for (int l = 0; l < jacobian.length; ++l) { for (int c = 0; c < jacobian[l].length; ++c) { jacobian[l][c] = field.getZero().add(1 + 0.1 * c); } } combined.getJacobian(CartesianDerivativesFilter.USE_PVA, jacobian); for (int j = 0; j < 100; ++j) { FieldPVCoordinates<T> pv0 = new FieldPVCoordinates<>(randomVector(field, 1e3, random), randomVector(field, 1.0, random), randomVector(field, 1.0e-3, random)); double epsilonP = 2.0e-12 * pv0.getPosition().getNorm().getReal(); double epsilonV = 6.0e-11 * pv0.getVelocity().getNorm().getReal(); double epsilonA = 2.0e-9 * pv0.getAcceleration().getNorm().getReal(); for (int c = 0; c < directions.length; ++c) { // eight points finite differences estimation of a Jacobian column FieldPVCoordinates<T> pvm4h = combined.transformPVCoordinates(new FieldPVCoordinates<>(1.0, pv0, -4 * h, directions[c])); FieldPVCoordinates<T> pvm3h = combined.transformPVCoordinates(new FieldPVCoordinates<>(1.0, pv0, -3 * h, directions[c])); FieldPVCoordinates<T> pvm2h = combined.transformPVCoordinates(new FieldPVCoordinates<>(1.0, pv0, -2 * h, directions[c])); FieldPVCoordinates<T> pvm1h = combined.transformPVCoordinates(new FieldPVCoordinates<>(1.0, pv0, -1 * h, directions[c])); FieldPVCoordinates<T> pvp1h = combined.transformPVCoordinates(new FieldPVCoordinates<>(1.0, pv0, +1 * h, directions[c])); FieldPVCoordinates<T> pvp2h = combined.transformPVCoordinates(new FieldPVCoordinates<>(1.0, pv0, +2 * h, directions[c])); FieldPVCoordinates<T> pvp3h = combined.transformPVCoordinates(new FieldPVCoordinates<>(1.0, pv0, +3 * h, directions[c])); FieldPVCoordinates<T> pvp4h = combined.transformPVCoordinates(new FieldPVCoordinates<>(1.0, pv0, +4 * h, directions[c])); FieldPVCoordinates<T> d4 = new FieldPVCoordinates<>(pvm4h, pvp4h); FieldPVCoordinates<T> d3 = new FieldPVCoordinates<>(pvm3h, pvp3h); FieldPVCoordinates<T> d2 = new FieldPVCoordinates<>(pvm2h, pvp2h); FieldPVCoordinates<T> d1 = new FieldPVCoordinates<>(pvm1h, pvp1h); double d = 1.0 / (840 * h); FieldPVCoordinates<T> estimatedColumn = new FieldPVCoordinates<>(-3 * d, d4, 32 * d, d3, -168 * d, d2, 672 * d, d1); // check analytical Jacobian against finite difference reference Assert.assertEquals(estimatedColumn.getPosition().getX().getReal(), jacobian[0][c].getReal(), epsilonP); Assert.assertEquals(estimatedColumn.getPosition().getY().getReal(), jacobian[1][c].getReal(), epsilonP); Assert.assertEquals(estimatedColumn.getPosition().getZ().getReal(), jacobian[2][c].getReal(), epsilonP); Assert.assertEquals(estimatedColumn.getVelocity().getX().getReal(), jacobian[3][c].getReal(), epsilonV); Assert.assertEquals(estimatedColumn.getVelocity().getY().getReal(), jacobian[4][c].getReal(), epsilonV); Assert.assertEquals(estimatedColumn.getVelocity().getZ().getReal(), jacobian[5][c].getReal(), epsilonV); Assert.assertEquals(estimatedColumn.getAcceleration().getX().getReal(), jacobian[6][c].getReal(), epsilonA); Assert.assertEquals(estimatedColumn.getAcceleration().getY().getReal(), jacobian[7][c].getReal(), epsilonA); Assert.assertEquals(estimatedColumn.getAcceleration().getZ().getReal(), jacobian[8][c].getReal(), epsilonA); } } } } @Test public void testLine() { doTestLine(Decimal64Field.getInstance()); } private <T extends RealFieldElement<T>> void doTestLine(Field<T> field) { RandomGenerator random = new Well19937a(0x4a5ff67426c5731fl); for (int i = 0; i < 100; ++i) { FieldTransform<T> transform = randomTransform(field, random); for (int j = 0; j < 20; ++j) { FieldVector3D<T> p0 = randomVector(field, 1.0e3, random); FieldVector3D<T> p1 = randomVector(field, 1.0e3, random); FieldLine<T> l = new FieldLine<>(p0, p1, 1.0e-10); FieldLine<T> transformed = transform.transformLine(l); for (int k = 0; k < 10; ++k) { FieldVector3D<T> p = l.pointAt(random.nextDouble() * 1.0e6); Assert.assertEquals(0.0, transformed.distance(transform.transformPosition(p)).getReal(), 1.0e-9); } } } } @Test public void testLineDouble() { doTestLineDouble(Decimal64Field.getInstance()); } private <T extends RealFieldElement<T>> void doTestLineDouble(Field<T> field) { RandomGenerator random = new Well19937a(0x4a5ff67426c5731fl); for (int i = 0; i < 100; ++i) { FieldTransform<T> transform = randomTransform(field, random); for (int j = 0; j < 20; ++j) { Vector3D p0 = randomVector(field, 1.0e3, random).toVector3D(); Vector3D p1 = randomVector(field, 1.0e3, random).toVector3D(); Line l = new Line(p0, p1, 1.0e-10); FieldLine<T> transformed = transform.transformLine(l); for (int k = 0; k < 10; ++k) { Vector3D p = l.pointAt(random.nextDouble() * 1.0e6); Assert.assertEquals(0.0, transformed.distance(transform.transformPosition(p)).getReal(), 1.0e-9); } } } } @Test public void testLinear() { doTestLinear(Decimal64Field.getInstance()); } private <T extends RealFieldElement<T>> void doTestLinear(final Field<T> field) { RandomGenerator random = new Well19937a(0x14f6411217b148d8l); for (int n = 0; n < 100; ++n) { FieldTransform<T> t = randomTransform(field, random); // build an equivalent linear transform by extracting raw translation/rotation FieldMatrix<T> linearA = MatrixUtils.createFieldMatrix(field, 3, 4); linearA.setSubMatrix(t.getRotation().getMatrix(), 0, 0); FieldVector3D<T> rt = t.getRotation().applyTo(t.getTranslation()); linearA.setEntry(0, 3, rt.getX()); linearA.setEntry(1, 3, rt.getY()); linearA.setEntry(2, 3, rt.getZ()); // build an equivalent linear transform by observing transformed points FieldMatrix<T> linearB = MatrixUtils.createFieldMatrix(field, 3, 4); FieldVector3D<T> p0 = t.transformPosition(FieldVector3D.getZero(field)); FieldVector3D<T> pI = t.transformPosition(FieldVector3D.getPlusI(field)).subtract(p0); FieldVector3D<T> pJ = t.transformPosition(FieldVector3D.getPlusJ(field)).subtract(p0); FieldVector3D<T> pK = t.transformPosition(FieldVector3D.getPlusK(field)).subtract(p0); linearB.setEntry(0, 0, pI.getX()); linearB.setEntry(1, 0, pI.getY()); linearB.setEntry(2, 0, pI.getZ()); linearB.setEntry(0, 1, pJ.getX()); linearB.setEntry(1, 1, pJ.getY()); linearB.setEntry(2, 1, pJ.getZ()); linearB.setEntry(0, 2, pK.getX()); linearB.setEntry(1, 2, pK.getY()); linearB.setEntry(2, 2, pK.getZ()); linearB.setEntry(0, 3, p0.getX()); linearB.setEntry(1, 3, p0.getY()); linearB.setEntry(2, 3, p0.getZ()); // both linear transforms should be equal FieldMatrix<T> sub = linearB.subtract(linearA); double refMax = 0; double diffMax = 0; for (int i = 0; i < linearA.getRowDimension(); ++i) { for (int j = 0; j < linearA.getColumnDimension(); ++j) { refMax = FastMath.max(linearA.getEntry(i, j).getReal(), refMax); diffMax = FastMath.max(sub.getEntry(i, j).getReal(), diffMax); } } Assert.assertEquals(0.0, diffMax, 2.0e-12 * refMax); for (int i = 0; i < 100; ++i) { FieldVector3D<T> p = randomVector(field, 1.0e3, random); FieldVector3D<T> q = t.transformPosition(p); T[] pField = MathArrays.buildArray(field, 4); pField[0] = p.getX(); pField[1] = p.getY(); pField[2] = p.getZ(); pField[3] = field.getOne(); T[] qA = linearA.operate(pField); Assert.assertEquals(q.getX().getReal(), qA[0].getReal(), 1.0e-13 * p.getNorm().getReal()); Assert.assertEquals(q.getY().getReal(), qA[1].getReal(), 1.0e-13 * p.getNorm().getReal()); Assert.assertEquals(q.getZ().getReal(), qA[2].getReal(), 1.0e-13 * p.getNorm().getReal()); T[] qB = linearB.operate(pField); Assert.assertEquals(q.getX().getReal(), qB[0].getReal(), 1.0e-10 * p.getNorm().getReal()); Assert.assertEquals(q.getY().getReal(), qB[1].getReal(), 1.0e-10 * p.getNorm().getReal()); Assert.assertEquals(q.getZ().getReal(), qB[2].getReal(), 1.0e-10 * p.getNorm().getReal()); } } } @Test public void testShift() { doTestShift(Decimal64Field.getInstance()); } private <T extends RealFieldElement<T>> void doTestShift(Field<T> field) { // the following transform corresponds to a frame moving along the line x=1 and rotating around its -z axis // the linear motion velocity is (0, +1, 0), the angular rate is PI/2 // at t = -1 the frame origin is at (1, -1, 0), its X axis is equal to Xref and its Y axis is equal to Yref // at t = 0 the frame origin is at (1, 0, 0), its X axis is equal to -Yref and its Y axis is equal to Xref // at t = +1 the frame origin is at (1, +1, 0), its X axis is equal to -Xref and its Y axis is equal to -Yref FieldAbsoluteDate<T> date = FieldAbsoluteDate.getGalileoEpoch(field); double alpha0 = 0.5 * FastMath.PI; double omega = 0.5 * FastMath.PI; FieldTransform<T> t = new FieldTransform<>(date, new FieldTransform<>(date, FieldVector3D.getMinusI(field), FieldVector3D.getMinusJ(field)), new FieldTransform<>(date, new FieldRotation<>(FieldVector3D.getPlusK(field), field.getZero().add(alpha0), RotationConvention.VECTOR_OPERATOR), new FieldVector3D<>(omega, FieldVector3D.getMinusK(field)))); for (double dt = -10.0; dt < 10.0; dt += 0.125) { FieldTransform<T> shifted = t.shiftedBy(dt); // the following point should always remain at moving frame origin FieldPVCoordinates<T> expectedFixedPoint = shifted.transformPVCoordinates(new FieldPVCoordinates<>(createVector(field, 1, dt, 0), FieldVector3D.getPlusJ(field), FieldVector3D.getZero(field))); checkVector(expectedFixedPoint.getPosition(), FieldVector3D.getZero(field), 1.0e-14); checkVector(expectedFixedPoint.getVelocity(), FieldVector3D.getZero(field), 1.0e-14); checkVector(expectedFixedPoint.getAcceleration(), FieldVector3D.getZero(field), 1.0e-14); // fixed frame origin apparent motion in moving frame FieldPVCoordinates<T> expectedApparentMotion = shifted.transformPVCoordinates(PVCoordinates.ZERO); double c = FastMath.cos(alpha0 + omega * dt); double s = FastMath.sin(alpha0 + omega * dt); FieldVector3D<T> referencePosition = createVector(field, -c + dt * s, -s - dt * c, 0); FieldVector3D<T> referenceVelocity = createVector(field, (1 + omega) * s + dt * omega * c, -(1 + omega) * c + dt * omega * s, 0); FieldVector3D<T> referenceAcceleration = createVector(field, omega * (2 + omega) * c - dt * omega * omega * s, omega * (2 + omega) * s + dt * omega * omega * c, 0); checkVector(expectedApparentMotion.getPosition(), referencePosition, 1.0e-14); checkVector(expectedApparentMotion.getVelocity(), referenceVelocity, 1.0e-14); checkVector(expectedApparentMotion.getAcceleration(), referenceAcceleration, 1.0e-14); } } @Test public void testShiftDerivatives() { doTestShiftDerivatives(Decimal64Field.getInstance()); } private <T extends RealFieldElement<T>> void doTestShiftDerivatives(Field<T> field) { RandomGenerator random = new Well19937a(0x5acda4f605aadce7l); for (int i = 0; i < 10; ++i) { FieldTransform<T> t = randomTransform(field, random); for (double dtD = -10.0; dtD < 10.0; dtD += 0.125) { T dt = field.getZero().add(dtD); FieldTransform<T> t0 = t.shiftedBy(dt); T v = t0.getVelocity().getNorm(); T a = t0.getAcceleration().getNorm(); T omega = t0.getRotationRate().getNorm(); T omegaDot = t0.getRotationAcceleration().getNorm(); // numerical derivatives T h = omega.reciprocal().multiply(0.01); FieldTransform<T> tm4h = t.shiftedBy(dt.subtract(h.multiply(4))); FieldTransform<T> tm3h = t.shiftedBy(dt.subtract(h.multiply(3))); FieldTransform<T> tm2h = t.shiftedBy(dt.subtract(h.multiply(2))); FieldTransform<T> tm1h = t.shiftedBy(dt.subtract(h.multiply(1))); FieldTransform<T> tp1h = t.shiftedBy(dt.add(h.multiply(1))); FieldTransform<T> tp2h = t.shiftedBy(dt.add(h.multiply(2))); FieldTransform<T> tp3h = t.shiftedBy(dt.add(h.multiply(3))); FieldTransform<T> tp4h = t.shiftedBy(dt.add(h.multiply(4))); T numXDot = derivative(h, tm4h.getTranslation().getX(), tm3h.getTranslation().getX(), tm2h.getTranslation().getX(), tm1h.getTranslation().getX(), tp1h.getTranslation().getX(), tp2h.getTranslation().getX(), tp3h.getTranslation().getX(), tp4h.getTranslation().getX()); T numYDot = derivative(h, tm4h.getTranslation().getY(), tm3h.getTranslation().getY(), tm2h.getTranslation().getY(), tm1h.getTranslation().getY(), tp1h.getTranslation().getY(), tp2h.getTranslation().getY(), tp3h.getTranslation().getY(), tp4h.getTranslation().getY()); T numZDot = derivative(h, tm4h.getTranslation().getZ(), tm3h.getTranslation().getZ(), tm2h.getTranslation().getZ(), tm1h.getTranslation().getZ(), tp1h.getTranslation().getZ(), tp2h.getTranslation().getZ(), tp3h.getTranslation().getZ(), tp4h.getTranslation().getZ()); T numXDot2 = derivative(h, tm4h.getVelocity().getX(), tm3h.getVelocity().getX(), tm2h.getVelocity().getX(), tm1h.getVelocity().getX(), tp1h.getVelocity().getX(), tp2h.getVelocity().getX(), tp3h.getVelocity().getX(), tp4h.getVelocity().getX()); T numYDot2 = derivative(h, tm4h.getVelocity().getY(), tm3h.getVelocity().getY(), tm2h.getVelocity().getY(), tm1h.getVelocity().getY(), tp1h.getVelocity().getY(), tp2h.getVelocity().getY(), tp3h.getVelocity().getY(), tp4h.getVelocity().getY()); T numZDot2 = derivative(h, tm4h.getVelocity().getZ(), tm3h.getVelocity().getZ(), tm2h.getVelocity().getZ(), tm1h.getVelocity().getZ(), tp1h.getVelocity().getZ(), tp2h.getVelocity().getZ(), tp3h.getVelocity().getZ(), tp4h.getVelocity().getZ()); T numQ0Dot = derivative(h, tm4h.getRotation().getQ0(), tm3h.getRotation().getQ0(), tm2h.getRotation().getQ0(), tm1h.getRotation().getQ0(), tp1h.getRotation().getQ0(), tp2h.getRotation().getQ0(), tp3h.getRotation().getQ0(), tp4h.getRotation().getQ0()); T numQ1Dot = derivative(h, tm4h.getRotation().getQ1(), tm3h.getRotation().getQ1(), tm2h.getRotation().getQ1(), tm1h.getRotation().getQ1(), tp1h.getRotation().getQ1(), tp2h.getRotation().getQ1(), tp3h.getRotation().getQ1(), tp4h.getRotation().getQ1()); T numQ2Dot = derivative(h, tm4h.getRotation().getQ2(), tm3h.getRotation().getQ2(), tm2h.getRotation().getQ2(), tm1h.getRotation().getQ2(), tp1h.getRotation().getQ2(), tp2h.getRotation().getQ2(), tp3h.getRotation().getQ2(), tp4h.getRotation().getQ2()); T numQ3Dot = derivative(h, tm4h.getRotation().getQ3(), tm3h.getRotation().getQ3(), tm2h.getRotation().getQ3(), tm1h.getRotation().getQ3(), tp1h.getRotation().getQ3(), tp2h.getRotation().getQ3(), tp3h.getRotation().getQ3(), tp4h.getRotation().getQ3()); T numOxDot = derivative(h, tm4h.getRotationRate().getX(), tm3h.getRotationRate().getX(), tm2h.getRotationRate().getX(), tm1h.getRotationRate().getX(), tp1h.getRotationRate().getX(), tp2h.getRotationRate().getX(), tp3h.getRotationRate().getX(), tp4h.getRotationRate().getX()); T numOyDot = derivative(h, tm4h.getRotationRate().getY(), tm3h.getRotationRate().getY(), tm2h.getRotationRate().getY(), tm1h.getRotationRate().getY(), tp1h.getRotationRate().getY(), tp2h.getRotationRate().getY(), tp3h.getRotationRate().getY(), tp4h.getRotationRate().getY()); T numOzDot = derivative(h, tm4h.getRotationRate().getZ(), tm3h.getRotationRate().getZ(), tm2h.getRotationRate().getZ(), tm1h.getRotationRate().getZ(), tp1h.getRotationRate().getZ(), tp2h.getRotationRate().getZ(), tp3h.getRotationRate().getZ(), tp4h.getRotationRate().getZ()); // theoretical derivatives T theXDot = t0.getVelocity().getX(); T theYDot = t0.getVelocity().getY(); T theZDot = t0.getVelocity().getZ(); T theXDot2 = t0.getAcceleration().getX(); T theYDot2 = t0.getAcceleration().getY(); T theZDot2 = t0.getAcceleration().getZ(); FieldRotation<T> r0 = t0.getRotation(); FieldVector3D<T> w = t0.getRotationRate(); FieldVector3D<T> q = new FieldVector3D<>(r0.getQ1(), r0.getQ2(), r0.getQ3()); FieldVector3D<T> qw = FieldVector3D.crossProduct(q, w); T theQ0Dot = FieldVector3D.dotProduct(q, w).multiply(-0.5); T theQ1Dot = r0.getQ0().multiply(w.getX()).add(qw.getX()).multiply(0.5); T theQ2Dot = r0.getQ0().multiply(w.getY()).add(qw.getY()).multiply(0.5); T theQ3Dot = r0.getQ0().multiply(w.getZ()).add(qw.getZ()).multiply(0.5); T theOxDot2 = t0.getRotationAcceleration().getX(); T theOyDot2 = t0.getRotationAcceleration().getY(); T theOzDot2 = t0.getRotationAcceleration().getZ(); // check consistency Assert.assertEquals(theXDot.getReal(), numXDot.getReal(), 1.0e-13 * v.getReal()); Assert.assertEquals(theYDot.getReal(), numYDot.getReal(), 1.0e-13 * v.getReal()); Assert.assertEquals(theZDot.getReal(), numZDot.getReal(), 1.0e-13 * v.getReal()); Assert.assertEquals(theXDot2.getReal(), numXDot2.getReal(), 1.0e-13 * a.getReal()); Assert.assertEquals(theYDot2.getReal(), numYDot2.getReal(), 1.0e-13 * a.getReal()); Assert.assertEquals(theZDot2.getReal(), numZDot2.getReal(), 1.0e-13 * a.getReal()); Assert.assertEquals(theQ0Dot.getReal(), numQ0Dot.getReal(), 1.0e-13 * omega.getReal()); Assert.assertEquals(theQ1Dot.getReal(), numQ1Dot.getReal(), 1.0e-13 * omega.getReal()); Assert.assertEquals(theQ2Dot.getReal(), numQ2Dot.getReal(), 1.0e-13 * omega.getReal()); Assert.assertEquals(theQ3Dot.getReal(), numQ3Dot.getReal(), 1.0e-13 * omega.getReal()); Assert.assertEquals(theOxDot2.getReal(), numOxDot.getReal(), 1.0e-12 * omegaDot.getReal()); Assert.assertEquals(theOyDot2.getReal(), numOyDot.getReal(), 1.0e-12 * omegaDot.getReal()); Assert.assertEquals(theOzDot2.getReal(), numOzDot.getReal(), 1.0e-12 * omegaDot.getReal()); } } } @Test public void testInterpolation() throws OrekitException { doTestInterpolation(Decimal64Field.getInstance()); } private <T extends RealFieldElement<T>> void doTestInterpolation(Field<T> field) throws OrekitException { FieldAbsoluteDate<T> t0 = FieldAbsoluteDate.getGalileoEpoch(field); List<FieldTransform<T>> sample = new ArrayList<FieldTransform<T>>(); for (int i = 0; i < 5; ++i) { sample.add(evolvingTransform(t0, i * 0.8)); } for (double dt = 0.1; dt <= 3.1; dt += 0.01) { FieldTransform<T> reference = evolvingTransform(t0, dt); FieldTransform<T> interpolated = FieldTransform.interpolate(reference.getFieldDate(), sample); FieldTransform<T> error = new FieldTransform<>(reference.getFieldDate(), reference, interpolated.getInverse()); Assert.assertEquals(0.0, error.getCartesian().getPosition().getNorm().getReal(), 4.0e-12); Assert.assertEquals(0.0, error.getCartesian().getVelocity().getNorm().getReal(), 3.0e-11); Assert.assertEquals(0.0, error.getCartesian().getAcceleration().getNorm().getReal(), 3.0e-10); Assert.assertEquals(0.0, error.getAngular().getRotation().getAngle().getReal(), 2.0e-10); Assert.assertEquals(0.0, error.getAngular().getRotationRate().getNorm().getReal(), 2.0e-09); Assert.assertEquals(0.0, error.getAngular().getRotationAcceleration().getNorm().getReal(), 8.0e-09); } } private <T extends RealFieldElement<T>> FieldTransform<T> evolvingTransform(final FieldAbsoluteDate<T> t0, final double dt) { // the following transform corresponds to a frame moving along the circle r = 1 // with its x axis always pointing to the reference frame center final Field<T> field = t0.getField(); final double omega = 0.2; final FieldAbsoluteDate<T> date = t0.shiftedBy(dt); final double cos = FastMath.cos(omega * dt); final double sin = FastMath.sin(omega * dt); return new FieldTransform<>(date, new FieldTransform<>(date, createVector(field, -cos, -sin, 0), createVector(field, omega * sin, -omega * cos, 0), createVector(field, omega * omega * cos, omega * omega * sin, 0)), new FieldTransform<>(date, new FieldRotation<>(FieldVector3D.getPlusK(field), field.getZero().add(FastMath.PI - omega * dt), RotationConvention.VECTOR_OPERATOR), new FieldVector3D<>(omega, FieldVector3D.getPlusK(field)))); } private <T extends RealFieldElement<T>> T derivative(T h, T ym4h, T ym3h, T ym2h, T ym1h, T yp1h, T yp2h, T yp3h, T yp4h) { return yp4h.subtract(ym4h).multiply( -3). add(yp3h.subtract(ym3h).multiply( 32)). add(yp2h.subtract(ym2h).multiply(-168)). add(yp1h.subtract(ym1h).multiply( 672)). divide(h.multiply(840)); } private <T extends RealFieldElement<T>> FieldTransform<T> randomTransform(Field<T> field, RandomGenerator random) { // generate a random transform FieldTransform<T> combined = FieldTransform.getIdentity(field); for (int k = 0; k < 20; ++k) { FieldTransform<T> t = random.nextBoolean() ? new FieldTransform<>(FieldAbsoluteDate.getJ2000Epoch(field), randomVector(field, 1.0e3, random), randomVector(field, 1.0, random), randomVector(field, 1.0e-3, random)) : new FieldTransform<>(FieldAbsoluteDate.getJ2000Epoch(field), randomRotation(field, random), randomVector(field, 0.01, random), randomVector(field, 1.0e-4, random)); combined = new FieldTransform<>(FieldAbsoluteDate.getJ2000Epoch(field), combined, t); } return combined; } private <T extends RealFieldElement<T>> FieldVector3D<T> randomVector(Field<T> field, double scale, RandomGenerator random) { return createVector(field, random.nextDouble() * scale, random.nextDouble() * scale, random.nextDouble() * scale); } private <T extends RealFieldElement<T>> FieldRotation<T> randomRotation(Field<T> field, RandomGenerator random) { double q0 = random.nextDouble() * 2 - 1; double q1 = random.nextDouble() * 2 - 1; double q2 = random.nextDouble() * 2 - 1; double q3 = random.nextDouble() * 2 - 1; return createRotation(field, q0, q1, q2, q3, true); } private <T extends RealFieldElement<T>> void checkNoTransform(FieldTransform<T> transform, RandomGenerator random) { for (int i = 0; i < 100; ++i) { FieldVector3D<T> a = randomVector(transform.getFieldDate().getField(), 1.0e3, random); FieldVector3D<T> tA = transform.transformVector(a); Assert.assertEquals(0, a.subtract(tA).getNorm().getReal(), 1.0e-10 * a.getNorm().getReal()); FieldVector3D<T> b = randomVector(transform.getFieldDate().getField(), 1.0e3, random); FieldVector3D<T> tB = transform.transformPosition(b); Assert.assertEquals(0, b.subtract(tB).getNorm().getReal(), 1.0e-10 * b.getNorm().getReal()); FieldPVCoordinates<T> pv = new FieldPVCoordinates<>(randomVector(transform.getFieldDate().getField(), 1.0e3, random), randomVector(transform.getFieldDate().getField(), 1.0, random), randomVector(transform.getFieldDate().getField(), 1.0e-3, random)); FieldPVCoordinates<T> tPv = transform.transformPVCoordinates(pv); checkVector(pv.getPosition(), tPv.getPosition(), 1.0e-10); checkVector(pv.getVelocity(), tPv.getVelocity(), 3.0e-9); checkVector(pv.getAcceleration(), tPv.getAcceleration(), 3.0e-9); } } private <T extends RealFieldElement<T>> void checkVector(FieldVector3D<T> reference, FieldVector3D<T> result, double relativeTolerance) { T refNorm = reference.getNorm(); T resNorm = result.getNorm(); double tolerance = relativeTolerance * (1 + FastMath.max(refNorm.getReal(), resNorm.getReal())); Assert.assertEquals("ref = " + reference + ", res = " + result + " -> " + (FieldVector3D.distance(reference, result).divide(1 + FastMath.max(refNorm.getReal(), resNorm.getReal()))), 0, FieldVector3D.distance(reference, result).getReal(), tolerance); } private <T extends RealFieldElement<T>> FieldVector3D<T> createVector(Field<T> field, double x, double y, double z) { return new FieldVector3D<>(field.getZero().add(x), field.getZero().add(y), field.getZero().add(z)); } private <T extends RealFieldElement<T>> FieldRotation<T> createRotation(Field<T> field, double q0, double q1, double q2, double q3, boolean needsNormalization) { return new FieldRotation<>(field.getZero().add(q0), field.getZero().add(q1), field.getZero().add(q2), field.getZero().add(q3), needsNormalization); } }