CreateKeplerianOrbitUsingParameters
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public class SimpleKeplerianOrbitUsingParameters {
public static void main(String[] args) throws PatriusException, IOException, ParseException {
// Patrius Dataset initialization (needed for example to get the UTC time)
PatriusDataset.addResourcesFromPatriusDataset() ;
// Recovery of the UTC time scale using a "factory" (not to duplicate such unique object)
final TimeScale TUC = TimeScalesFactory.getUTC();
// Date of the orbit given in UTC time scale)
final AbsoluteDate date = new AbsoluteDate("2010-01-01T12:00:00.000", TUC);
// Getting the frame with wich will defined the orbit parameters
// As for time scale, we will use also a "factory".
final Frame GCRF = FramesFactory.getGCRF();
// Creation of a keplerian orbit
final double sma = 7200.e+3;
final double exc = 0.01;
final double inc = FastMath.toRadians(98.);
final double pa = FastMath.toRadians(0.);
final double raan = FastMath.toRadians(0.);
final double anm = FastMath.toRadians(0.);
final double MU = Constants.WGS84_EARTH_MU;
// We use firstly an orbital parameters object
final KeplerianParameters kep = new KeplerianParameters(sma, exc, inc, pa, raan, anm, PositionAngle.MEAN, MU);
// Then, we create the orbit
final KeplerianOrbit iniOrbit = new KeplerianOrbit(kep, GCRF, date);
// Printing the Keplerian period
System.out.println("Tper = "+iniOrbit.getKeplerianPeriod()+" s");
// We may use other set of parameters ...
final double per = sma*(1.-exc);
final double apo = sma*(1.+exc);
final ApsisRadiusParameters aps = new ApsisRadiusParameters(per, apo, inc, pa, raan, anm, PositionAngle.MEAN, MU);
// Then, we create again the orbit
final KeplerianOrbit sameOrbit = new KeplerianOrbit(aps, GCRF, date);
// We compare each PV coordinates
final PVCoordinates pvOrbit = iniOrbit.getPVCoordinates();
final PVCoordinates pvSameOrbit = sameOrbit.getPVCoordinates();
System.out.println();
System.out.println("Is both orbits equals : "+pvSameOrbit.getPosition().equals(pvOrbit.getPosition()));
System.out.println("Is both orbits equals : "+pvSameOrbit.getVelocity().equals(pvOrbit.getVelocity()));
}
}