Jacobian of the Cartesian orbital parameters with respect to the Equinoctial parameters

Orekit usage
1

Hi all,

Do you know how to compute the Jacobian of the Cartesian orbital parameters (i.e. x, y, z, xDot, yDot, zDot) with respect to the Equinoctial parameters with true angle (i.e. a, eX, eY, hX, hY, l)?
Basically, I need the following matrix:

[  dx/da,   dy/da,   dz/da,   dxDot/da,   dyDot/da,   dzDot/da
  dx/deX,  dy/deX,  dz/deX,  dxDot/deX,  dyDot/deX,  dzDot/deX 
  dx/deY,  dy/deY,  dz/deY,  dxDot/deY,  dyDot/deY,  dzDot/deY 
  dx/dhX,  dy/dhX,  dz/dhX,  dxDot/dhX,  dyDot/dhX,  dzDot/dhX
  dx/dgY,  dy/dhY,  dz/dhY,  dxDot/dhY,  dyDot/dhY,  dzDot/dhY 
   dx/dl,   dy/dl,   dz/dl,   dxDot/dl,   dyDot/dl,   dzDot/dl ]

Thank you in advance for your help.

Kind regards,

B.

2

Hi,

You can something like:

        final double[][] aCY = new double[6][6];
        orbit.getJacobianWrtParameters(PositionAngle.TRUE, aCY);
        final RealMatrix dCdY = new Array2DRowRealMatrix(aCY, false);

Were orbit is an EquinoctialOrbit object.

Kind regards,
Bryan

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