Example usage for org.apache.commons.math3.complex Quaternion multiply

Introduction

In this page you can find the example usage for org.apache.commons.math3.complex Quaternion multiply.

Prototype

public Quaternion multiply(final double alpha) 

Source Link

Document

Multiplies the instance by a scalar.

Usage

From source file:etomica.virial.MCMoveClusterRingRegrowOrientation.java

public void rotateVectorV(double angle, IVector axis, IVectorMutable v) {
    double q0 = Math.cos(angle / 2.0);
    double sth2 = Math.sin(angle / 2.0);
    IVectorMutable a1 = space.makeVector();
    a1.E(axis);/* w w w  .  jav a2s  .  co m*/
    a1.TE(sth2);
    double q1 = a1.getX(0);
    double q2 = a1.getX(1);
    double q3 = a1.getX(2);
    Quaternion q = new Quaternion(q0, q1, q2, q3);
    Quaternion vec = new Quaternion(0, v.getX(0), v.getX(1), v.getX(2));
    Quaternion w = q.multiply(vec).multiply(q.getConjugate());
    if (Math.abs(w.getScalarPart()) > 1E-10)
        throw new RuntimeException("Quaternion product is not a vector!");
    v.E(w.getVectorPart());
}

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From source file:sceneGraph.Rot.java

/** Get the swing rotation and twist rotation for the specified axis. The twist rotation represents the rotation around the
 * specified axis. The swing rotation represents the rotation of the specified axis itself, which is the rotation around an
 * axis perpendicular to the specified axis. </p> The swing and twist rotation can be used to reconstruct the original
 * quaternion: this = swing * twist/*from   w w  w .j a v  a  2s.  c o  m*/
 * 
 * @param axisX the X component of the normalized axis for which to get the swing and twist rotation
 * @param axisY the Y component of the normalized axis for which to get the swing and twist rotation
 * @param axisZ the Z component of the normalized axis for which to get the swing and twist rotation
 * @return an Array of Rot objects. With the first element representing the swing, and the second representing the twist
 * @see <a href="http://www.euclideanspace.com/maths/geometry/rotations/for/decomposition">calculation</a> */
public Rot[] getSwingTwist(DVector axis) {
    Quaternion thisQ = new Quaternion(rotation.getQ0(), rotation.getQ1(), rotation.getQ2(), rotation.getQ3());
    double d = new DVector(thisQ.getQ1(), thisQ.getQ2(), thisQ.getQ3()).dot(axis);
    Quaternion twist = new Quaternion(rotation.getQ0(), axis.x * d, axis.y * d, axis.z * d).normalize();
    if (d < 0)
        twist.multiply(-1f);
    Quaternion swing = twist.getConjugate();
    swing = Quaternion.multiply(thisQ, swing);

    Rot[] result = new Rot[2];

    result[0] = new Rot(new Rotation(swing.getQ0(), swing.getQ1(), swing.getQ2(), swing.getQ3(), true));
    result[1] = new Rot(new Rotation(twist.getQ0(), twist.getQ1(), twist.getQ2(), twist.getQ3(), true));

    return result;
}

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