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.frames; import java.util.Random; import org.apache.commons.math3.geometry.euclidean.threed.Rotation; import org.apache.commons.math3.geometry.euclidean.threed.Vector3D; import org.apache.commons.math3.util.FastMath; import org.junit.Assert; import org.junit.Before; import org.junit.Test; import org.orekit.Utils; import org.orekit.bodies.GeodeticPoint; import org.orekit.bodies.OneAxisEllipsoid; import org.orekit.errors.OrekitException; import org.orekit.time.AbsoluteDate; import org.orekit.time.TimeScalesFactory; import org.orekit.utils.Constants; import org.orekit.utils.IERSConventions; import org.orekit.utils.PVCoordinates; public class FrameTest { @Test public void testSameFrameRoot() throws OrekitException { Random random = new Random(0x29448c7d58b95565l); Frame frame = FramesFactory.getEME2000(); checkNoTransform(frame.getTransformTo(frame, new AbsoluteDate()), random); Assert.assertTrue(frame.getDepth() > 0); Assert.assertEquals(frame.getParent().getDepth() + 1, frame.getDepth()); } @Test public void testSameFrameNoRoot() throws OrekitException { Random random = new Random(0xc6e88d0f53e29116l); Transform t = randomTransform(random); Frame frame = new Frame(FramesFactory.getEME2000(), t, null, true); checkNoTransform(frame.getTransformTo(frame, new AbsoluteDate()), random); } @Test public void testSimilarFrames() throws OrekitException { Random random = new Random(0x1b868f67a83666e5l); Transform t = randomTransform(random); Frame frame1 = new Frame(FramesFactory.getEME2000(), t, null, true); Frame frame2 = new Frame(FramesFactory.getEME2000(), t, null, false); checkNoTransform(frame1.getTransformTo(frame2, new AbsoluteDate()), random); } @Test public void testFromParent() throws OrekitException { Random random = new Random(0xb92fba1183fe11b8l); Transform fromEME2000 = randomTransform(random); Frame frame = new Frame(FramesFactory.getEME2000(), fromEME2000, null); Transform toEME2000 = frame.getTransformTo(FramesFactory.getEME2000(), new AbsoluteDate()); checkNoTransform(new Transform(fromEME2000.getDate(), fromEME2000, toEME2000), random); } @Test public void testDecomposedTransform() throws OrekitException { Random random = new Random(0xb7d1a155e726da57l); Transform t1 = randomTransform(random); Transform t2 = randomTransform(random); Transform t3 = randomTransform(random); Frame frame1 = new Frame(FramesFactory.getEME2000(), new Transform(t1.getDate(), new Transform(t1.getDate(), t1, t2), t3), null); Frame frame2 = new Frame(new Frame(new Frame(FramesFactory.getEME2000(), t1, null), t2, null), t3, null); checkNoTransform(frame1.getTransformTo(frame2, new AbsoluteDate()), random); } @Test public void testFindCommon() throws OrekitException { Random random = new Random(0xb7d1a155e726da57l); Transform t1 = randomTransform(random); Transform t2 = randomTransform(random); Transform t3 = randomTransform(random); Frame R1 = new Frame(FramesFactory.getEME2000(), t1, "R1"); Frame R2 = new Frame(R1, t2, "R2"); Frame R3 = new Frame(R2, t3, "R3"); Assert.assertTrue(R1.getDepth() > 0); Assert.assertEquals(R1.getDepth() + 1, R2.getDepth()); Assert.assertEquals(R2.getDepth() + 1, R3.getDepth()); Transform T = R1.getTransformTo(R3, new AbsoluteDate()); Transform S = new Transform(t2.getDate(), t2, t3); checkNoTransform(new Transform(T.getDate(), T, S.getInverse()), random); } @Test public void testDepthAndAncestor() throws OrekitException { Random random = new Random(0x01f8d3b944123044l); Frame root = Frame.getRoot(); Frame f1 = new Frame(root, randomTransform(random), "f1"); Frame f2 = new Frame(f1, randomTransform(random), "f2"); Frame f3 = new Frame(f1, randomTransform(random), "f3"); Frame f4 = new Frame(f2, randomTransform(random), "f4"); Frame f5 = new Frame(f3, randomTransform(random), "f5"); Frame f6 = new Frame(f5, randomTransform(random), "f6"); Assert.assertEquals(0, root.getDepth()); Assert.assertEquals(1, f1.getDepth()); Assert.assertEquals(2, f2.getDepth()); Assert.assertEquals(2, f3.getDepth()); Assert.assertEquals(3, f4.getDepth()); Assert.assertEquals(3, f5.getDepth()); Assert.assertEquals(4, f6.getDepth()); Assert.assertTrue(root == f1.getAncestor(1)); Assert.assertTrue(root == f6.getAncestor(4)); Assert.assertTrue(f1 == f6.getAncestor(3)); Assert.assertTrue(f3 == f6.getAncestor(2)); Assert.assertTrue(f5 == f6.getAncestor(1)); Assert.assertTrue(f6 == f6.getAncestor(0)); try { f6.getAncestor(5); Assert.fail("an exception should have been triggered"); } catch (IllegalArgumentException iae) { // expected behavior } catch (Exception e) { Assert.fail("wrong exception caught: " + e.getClass().getName()); } } @Test public void testIsChildOf() throws OrekitException { Random random = new Random(0xb7d1a155e726da78l); Frame eme2000 = FramesFactory.getEME2000(); Frame f1 = new Frame(eme2000, randomTransform(random), "f1"); Frame f2 = new Frame(f1, randomTransform(random), "f2"); Frame f4 = new Frame(f2, randomTransform(random), "f4"); Frame f5 = new Frame(f4, randomTransform(random), "f5"); Frame f6 = new Frame(eme2000, randomTransform(random), "f6"); Frame f7 = new Frame(f6, randomTransform(random), "f7"); Frame f8 = new Frame(f6, randomTransform(random), "f8"); Frame f9 = new Frame(f7, randomTransform(random), "f9"); // check if the root frame can be an ancestor of another frame Assert.assertEquals(false, eme2000.isChildOf(f5)); // check if a frame which belongs to the same branch than the 2nd frame is a branch of it Assert.assertEquals(true, f5.isChildOf(f1)); // check if a random frame is the child of the root frame Assert.assertEquals(true, f9.isChildOf(eme2000)); // check that a frame is not its own child Assert.assertEquals(false, f4.isChildOf(f4)); // check if a frame which belongs to a different branch than the 2nd frame can be a child for it Assert.assertEquals(false, f9.isChildOf(f5)); // check if the root frame is not a child of itself Assert.assertEquals(false, eme2000.isChildOf(eme2000)); Assert.assertEquals(false, f9.isChildOf(f8)); } @Test public void testH0m9() throws OrekitException { AbsoluteDate h0 = new AbsoluteDate("2010-07-01T10:42:09", TimeScalesFactory.getUTC()); Frame itrf = FramesFactory.getITRF(IERSConventions.IERS_2010, true); Frame rotatingPadFrame = new TopocentricFrame( new OneAxisEllipsoid(Constants.WGS84_EARTH_EQUATORIAL_RADIUS, Constants.WGS84_EARTH_FLATTENING, itrf), new GeodeticPoint(FastMath.toRadians(5.0), FastMath.toRadians(-100.0), 0.0), "launch pad"); // create a new inertially oriented frame that is aligned with ITRF2005 at h0 - 9 seconds AbsoluteDate h0M9 = h0.shiftedBy(-9.0); Frame eme2000 = FramesFactory.getEME2000(); Frame frozenLaunchFrame = rotatingPadFrame.getFrozenFrame(eme2000, h0M9, "launch frame"); // check velocity module is unchanged Vector3D pEme2000 = new Vector3D(-29536113.0, 30329259.0, -100125.0); Vector3D vEme2000 = new Vector3D(-2194.0, -2141.0, -8.0); PVCoordinates pvEme2000 = new PVCoordinates(pEme2000, vEme2000); PVCoordinates pvH0m9 = eme2000.getTransformTo(frozenLaunchFrame, h0M9).transformPVCoordinates(pvEme2000); Assert.assertEquals(vEme2000.getNorm(), pvH0m9.getVelocity().getNorm(), 1.0e-6); // this frame is fixed with respect to EME2000 but rotates with respect to the non-frozen one // the following loop should have a fixed angle a1 and an evolving angle a2 double minA1 = Double.POSITIVE_INFINITY; double maxA1 = Double.NEGATIVE_INFINITY; double minA2 = Double.POSITIVE_INFINITY; double maxA2 = Double.NEGATIVE_INFINITY; double dt; for (dt = 0; dt < 86164; dt += 300.0) { AbsoluteDate date = h0M9.shiftedBy(dt); double a1 = frozenLaunchFrame.getTransformTo(eme2000, date).getRotation().getAngle(); double a2 = frozenLaunchFrame.getTransformTo(rotatingPadFrame, date).getRotation().getAngle(); minA1 = FastMath.min(minA1, a1); maxA1 = FastMath.max(maxA1, a1); minA2 = FastMath.min(minA2, a2); maxA2 = FastMath.max(maxA2, a2); } Assert.assertEquals(0, maxA1 - minA1, 1.0e-12); Assert.assertEquals(FastMath.PI, maxA2 - minA2, 0.01); } private Transform randomTransform(Random random) { Transform transform = Transform.IDENTITY; for (int i = random.nextInt(10); i > 0; --i) { if (random.nextBoolean()) { Vector3D u = new Vector3D(random.nextDouble() * 1000.0, random.nextDouble() * 1000.0, random.nextDouble() * 1000.0); transform = new Transform(transform.getDate(), transform, new Transform(transform.getDate(), u)); } else { double q0 = random.nextDouble() * 2 - 1; double q1 = random.nextDouble() * 2 - 1; double q2 = random.nextDouble() * 2 - 1; double q3 = random.nextDouble() * 2 - 1; double q = FastMath.sqrt(q0 * q0 + q1 * q1 + q2 * q2 + q3 * q3); Rotation r = new Rotation(q0 / q, q1 / q, q2 / q, q3 / q, false); transform = new Transform(transform.getDate(), transform, new Transform(transform.getDate(), r)); } } return transform; } private void checkNoTransform(Transform transform, Random random) { for (int i = 0; i < 100; ++i) { Vector3D a = new Vector3D(random.nextDouble(), random.nextDouble(), random.nextDouble()); Vector3D b = transform.transformVector(a); Assert.assertEquals(0, a.subtract(b).getNorm(), 1.0e-10); Vector3D c = transform.transformPosition(a); Assert.assertEquals(0, a.subtract(c).getNorm(), 1.0e-10); } } @Before public void setUp() { Utils.setDataRoot("compressed-data"); } }