Re: [Orekit Users] Matlab

[Luc Maisonobe <Luc.Maisonobe@c-s.fr>]

Le 10/01/2018 à 11:45, Philippe Demoulin a écrit :
> Hello,

Hi Philippe,

> 
> I am currently testing if I could use Orekit from Matlab.  All the tests
> I made seem to work well, except that I did not succeed in implementing
> a step handler in Matlab.  Could somebody provide me a simple example ?
> For example, how to translate the following code ?

I was going to suggest you to look at Rami Houdroge application ISS
tracker
<https://fr.mathworks.com/matlabcentral/fileexchange/42733-isstracker-v1-0-0>
but it seems you already found it. Perhaps Rami
will be able to answer (I think he is on this list).

There was also a contribution from Issam Boukerch who interfaced Rugged
and Orekit in Matlab (see
<https://www.orekit.org/forge/projects/rugged/wiki/MatlabExample>) but
in this contribution, there are no Matlab
implementation of a Java interface.

best regards,
Luc

> 
> Main code in Matlab :
> 
> date = AbsoluteDate(2003, 9, 16, TimeScalesFactory.getUTC());
> eme2000 = FramesFactory.getEME2000();
> orbit = KeplerianOrbit(a, e, i, pa, raan, anomaly, ...
>     PositionAngle.TRUE, eme2000, date, Constants.EIGEN5C_EARTH_MU);
> propagator = KeplerianPropagator(orbit);
> propagator.setMasterMode(60.0, GroundTrackPrinter());
> propagator.propagate(date.shiftedBy(10000.0));
> 
> Handler GroundTrackPrinter() in Java :
> 
> public class GroundTrackPrinter implements OrekitFixedStepHandler {
>    private BodyShape earth;
>    public GroundTrackPrinter() throws OrekitException {
>       earth = new OneAxisEllipsoid(
>          Constants.WGS84_EARTH_EQUATORIAL_RADIUS,
>          Constants.WGS84_EARTH_FLATTENING,
>          FramesFactory.getITRF(IERSConventions.IERS_2010,true) );
>    }
>    public void handleStep(SpacecraftState currentState, boolean isLast)
>       throws OrekitException {
>       AbsoluteDate date = currentState.getDate();
>       Frame frame = earth.getBodyFrame();
>       Vector3D position =
>          currentState.getPVCoordinates(frame).getPosition();
>       GeodeticPoint gp = earth.transform(position, frame, date);
>       System.out.format( Locale.US, "%s %6.2f %6.2f %9.1f%n",
>          date, gp.getLatitude(), gp.getLongitude(), getAltitude() );
>       if (isLast) {
>          System.out.println("end of propagation");
>       }
>    }
> 
> Thanks in advance for your help.
> 
> Best regards,
> 
> Philippe Demoulin
> -----------------------------------------------
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> +32 2 373 0421
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