Example usage for org.apache.commons.math3.geometry.euclidean.threed FieldVector3D angle

Introduction

In this page you can find the example usage for org.apache.commons.math3.geometry.euclidean.threed FieldVector3D angle.

Prototype

public static <T extends RealFieldElement<T>> T angle(final Vector3D v1, final FieldVector3D<T> v2)
        throws MathArithmeticException 

Source Link

Document

Compute the angular separation between two vectors.

Usage

From source file:org.orekit.utils.TimeStampedFieldAngularCoordinatesTest.java

@Test
public void testRodriguesSpecialCases()
        throws NoSuchMethodException, IllegalAccessException, InvocationTargetException {

    // use reflection to test the private static methods
    Method getter = TimeStampedFieldAngularCoordinates.class.getDeclaredMethod("getModifiedRodrigues",
            new Class<?>[] { TimeStampedFieldAngularCoordinates.class, double[].class, double.class });
    getter.setAccessible(true);/*from  www.  j  a v a 2s.c  o  m*/
    Method factory = TimeStampedFieldAngularCoordinates.class.getDeclaredMethod("createFromModifiedRodrigues",
            new Class<?>[] { RealFieldElement[][].class, TimeStampedFieldAngularCoordinates.class });
    factory.setAccessible(true);

    // identity
    DerivativeStructure[][] identity = (DerivativeStructure[][]) getter.invoke(null, identity(),
            new double[] { 1.0, 0.0, 0.0, 0.0 }, -0.9999);
    @SuppressWarnings("unchecked")
    TimeStampedFieldAngularCoordinates<DerivativeStructure> acId = (TimeStampedFieldAngularCoordinates<DerivativeStructure>) factory
            .invoke(null, identity, identity());
    for (DerivativeStructure element : identity[0]) {
        Assert.assertEquals(0.0, element.getReal(), Precision.SAFE_MIN);
    }
    for (DerivativeStructure element : identity[1]) {
        Assert.assertEquals(0.0, element.getReal(), Precision.SAFE_MIN);
    }
    Assert.assertEquals(0.0, acId.getRotation().getAngle().getReal(), Precision.SAFE_MIN);
    Assert.assertEquals(0.0, acId.getRotationRate().getNorm().getReal(), Precision.SAFE_MIN);

    // PI angle FieldRotation<DerivativeStructure> (which is singular for non-modified Rodrigues vector)
    Random random = new Random(0x2158523e6accb859l);
    double[] previous = new double[] { 1.0, 0.0, 0.0, 0.0 };
    for (int i = 0; i < 100; ++i) {
        FieldVector3D<DerivativeStructure> axis = randomVector(random, 1.0);
        DerivativeStructure[][] piRotation = (DerivativeStructure[][]) getter.invoke(null,
                new TimeStampedFieldAngularCoordinates<DerivativeStructure>(AbsoluteDate.J2000_EPOCH,
                        createRotation(axis, FastMath.PI), createVector(0, 0, 0, 4), createVector(0, 0, 0, 4)),
                previous, -0.9999);
        @SuppressWarnings("unchecked")
        TimeStampedFieldAngularCoordinates<DerivativeStructure> acPi = (TimeStampedFieldAngularCoordinates<DerivativeStructure>) factory
                .invoke(null, piRotation, identity());
        Assert.assertEquals(FastMath.PI, acPi.getRotation().getAngle().getReal(), 1.0e-15);
        Assert.assertEquals(0.0, FieldVector3D.angle(axis, acPi.getRotation().getAxis()).sin().getReal(),
                1.0e-15);
        Assert.assertEquals(0.0, acPi.getRotationRate().getNorm().getReal(), 1.0e-16);
    }

    // 2 PI angle FieldRotation<DerivativeStructure> (which is singular for modified Rodrigues vector)
    Assert.assertNull(getter.invoke(null, identity(), new double[] { -1.0, 0.0, 0.0, 0.0 }, -0.9999));
    Assert.assertNotNull(getter.invoke(null, identity(), new double[] { +1.0, 0.0, 0.0, 0.0 }, -0.9999));

}

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