jat.examples.ephemeris.DE405PropagateText.java Source code

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Here is the source code for jat.examples.ephemeris.DE405PropagateText.java

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/* JAT: Java Astrodynamics Toolkit
 * 
  Copyright 2012 Tobias Berthold
    
   Licensed 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 jat.examples.ephemeris;

import jat.core.ephemeris.DE405Body.body;
import jat.core.ephemeris.DE405Frame;
import jat.core.ephemeris.DE405Plus;
import jat.core.spacetime.TimeAPL;
import jat.core.util.PathUtil;

import org.apache.commons.math3.ode.FirstOrderDifferentialEquations;
import org.apache.commons.math3.ode.FirstOrderIntegrator;
import org.apache.commons.math3.ode.nonstiff.DormandPrince853Integrator;

public class DE405PropagateText {
    static boolean print = false;

    void doExample() {
        //double tf = 10000000.;
        double tf = 3600 * 24 * 500;
        double[] y = { 2e8, 0, 0, 0, 24.2, 0 }; // initial state

        PathUtil path = new PathUtil();
        DE405Plus Eph = new DE405Plus(path);
        Eph.setFrame(DE405Frame.frame.HEE);
        Eph.printSteps = true;
        TimeAPL myTime = new TimeAPL(2003, 3, 1, 12, 0, 0);
        Eph.setIntegrationStartTime(myTime);
        Eph.bodyGravOnOff[body.SUN.ordinal()] = true;
        FirstOrderIntegrator dp853 = new DormandPrince853Integrator(1.0e-8, tf / 10.0, 1.0e-10, 1.0e-10);
        dp853.addStepHandler(Eph.stepHandler);
        FirstOrderDifferentialEquations ode = Eph;

        dp853.integrate(ode, 0.0, y, tf, y); // now y contains final state
        // at
        // time tf
        if (print) {
            String nf = "%10.3f ";
            String format = nf + nf + nf + nf + nf;
            System.out.printf(format, tf, y[0], y[1], y[2], Eph.energy(tf, y));
            System.out.println();
        }
    }

    public static void main(String[] args) {

        DE405PropagateText ex = new DE405PropagateText();
        ex.doExample();

    }

}