Example usage for org.apache.commons.math3.analysis.differentiation DerivativeStructure reciprocal

Introduction

In this page you can find the example usage for org.apache.commons.math3.analysis.differentiation DerivativeStructure reciprocal.

Prototype

public DerivativeStructure reciprocal() 

Source Link

Usage

From source file:org.orekit.forces.BoxAndSolarArraySpacecraft.java

/** {@inheritDoc} */
public FieldVector3D<DerivativeStructure> radiationPressureAcceleration(final AbsoluteDate date,
        final Frame frame, final FieldVector3D<DerivativeStructure> position,
        final FieldRotation<DerivativeStructure> rotation, final DerivativeStructure mass,
        final FieldVector3D<DerivativeStructure> flux) throws OrekitException {

    if (flux.getNormSq().getValue() < Precision.SAFE_MIN) {
        // null illumination (we are probably in umbra)
        return new FieldVector3D<DerivativeStructure>(0.0, flux);
    }// w  ww . jav a 2s  . c om

    // radiation flux in spacecraft frame
    final FieldVector3D<DerivativeStructure> fluxSat = rotation.applyTo(flux);

    // solar array contribution
    FieldVector3D<DerivativeStructure> normal = getNormal(date, frame, position, rotation);
    DerivativeStructure dot = FieldVector3D.dotProduct(normal, fluxSat);
    if (dot.getValue() > 0) {
        // the solar array is illuminated backward,
        // fix signs to compute contribution correctly
        dot = dot.negate();
        normal = normal.negate();
    }
    FieldVector3D<DerivativeStructure> force = facetRadiationAcceleration(normal, solarArrayArea, fluxSat, dot);

    // body facets contribution
    for (final Facet bodyFacet : facets) {
        normal = new FieldVector3D<DerivativeStructure>(mass.getField().getOne(), bodyFacet.getNormal());
        dot = FieldVector3D.dotProduct(normal, fluxSat);
        if (dot.getValue() < 0) {
            // the facet intercepts the incoming flux
            force = force.add(facetRadiationAcceleration(normal, bodyFacet.getArea(), fluxSat, dot));
        }
    }

    // convert to inertial frame
    return rotation.applyInverseTo(new FieldVector3D<DerivativeStructure>(mass.reciprocal(), force));

}

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From source file:org.orekit.forces.gravity.Relativity.java

@Override
public FieldVector3D<DerivativeStructure> accelerationDerivatives(final AbsoluteDate date, final Frame frame,
        final FieldVector3D<DerivativeStructure> position, final FieldVector3D<DerivativeStructure> velocity,
        final FieldRotation<DerivativeStructure> rotation, final DerivativeStructure mass) {

    //radius//from  w  w w .  j  av a 2 s.  c o  m
    final DerivativeStructure r2 = position.getNormSq();
    final DerivativeStructure r = r2.sqrt();
    //speed squared
    final DerivativeStructure s2 = velocity.getNormSq();
    final double c2 = Constants.SPEED_OF_LIGHT * Constants.SPEED_OF_LIGHT;
    //eq. 3.146
    return new FieldVector3D<DerivativeStructure>(r.reciprocal().multiply(4 * this.gm).subtract(s2), position,
            position.dotProduct(velocity).multiply(4), velocity)
                    .scalarMultiply(r2.multiply(r).multiply(c2).reciprocal().multiply(this.gm));

}

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From source file:org.orekit.forces.maneuvers.ConstantThrustManeuver.java

/** {@inheritDoc} */
public FieldVector3D<DerivativeStructure> accelerationDerivatives(final AbsoluteDate date, final Frame frame,
        final FieldVector3D<DerivativeStructure> position, final FieldVector3D<DerivativeStructure> velocity,
        final FieldRotation<DerivativeStructure> rotation, final DerivativeStructure mass)
        throws OrekitException {
    if (firing) {
        return new FieldVector3D<DerivativeStructure>(mass.reciprocal().multiply(thrust),
                rotation.applyInverseTo(direction));
    } else {//from   www.  ja  v  a2  s .c  o  m
        // constant (and null) acceleration when not firing
        final int parameters = mass.getFreeParameters();
        final int order = mass.getOrder();
        return new FieldVector3D<DerivativeStructure>(new DerivativeStructure(parameters, order, 0.0),
                new DerivativeStructure(parameters, order, 0.0),
                new DerivativeStructure(parameters, order, 0.0));
    }
}

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From source file:org.orekit.forces.radiation.SolarRadiationPressure.java

/** {@inheritDoc} */
public FieldVector3D<DerivativeStructure> accelerationDerivatives(final AbsoluteDate date, final Frame frame,
        final FieldVector3D<DerivativeStructure> position, final FieldVector3D<DerivativeStructure> velocity,
        final FieldRotation<DerivativeStructure> rotation, final DerivativeStructure mass)
        throws OrekitException {

    final FieldVector3D<DerivativeStructure> sunSatVector = position
            .subtract(sun.getPVCoordinates(date, frame).getPosition());
    final DerivativeStructure r2 = sunSatVector.getNormSq();

    // compute flux
    final double ratio = getLightningRatio(position.toVector3D(), frame, date);
    final DerivativeStructure rawP = r2.reciprocal().multiply(kRef * ratio);
    final FieldVector3D<DerivativeStructure> flux = new FieldVector3D<DerivativeStructure>(
            rawP.divide(r2.sqrt()), sunSatVector);

    // compute acceleration with all its partial derivatives
    return spacecraft.radiationPressureAcceleration(date, frame, position, rotation, mass, flux);

}

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From source file:org.orekit.forces.SphericalSpacecraft.java

/** {@inheritDoc} */
public FieldVector3D<DerivativeStructure> radiationPressureAcceleration(final AbsoluteDate date,
        final Frame frame, final FieldVector3D<DerivativeStructure> position,
        final FieldRotation<DerivativeStructure> rotation, final DerivativeStructure mass,
        final FieldVector3D<DerivativeStructure> flux) {
    final double kP = crossSection * (1 + 4 * (1.0 - absorptionCoeff) * (1.0 - specularReflectionCoeff) / 9.0);
    return new FieldVector3D<DerivativeStructure>(mass.reciprocal().multiply(kP), flux);
}

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