fk5hip¶

FK5 to Hipparcos rotation and spin.

Returns:

r5hdouble array
s5hdouble array

Notes

Wraps ERFA function eraFk5hip. The ERFA documentation is:

- - - - - - - - - -
 e r a F k 5 h i p
- - - - - - - - - -

FK5 to Hipparcos rotation and spin.

Returned:
   r5h   double[3][3]  r-matrix: FK5 rotation wrt Hipparcos (Note 2)
   s5h   double[3]     r-vector: FK5 spin wrt Hipparcos (Note 3)

Notes:

1) This function models the FK5 to Hipparcos transformation as a
   pure rotation and spin;  zonal errors in the FK5 catalog are not
   taken into account.

2) The r-matrix r5h operates in the sense:

         P_Hipparcos = r5h x P_FK5

   where P_FK5 is a p-vector in the FK5 frame, and P_Hipparcos is
   the equivalent Hipparcos p-vector.

3) The r-vector s5h represents the time derivative of the FK5 to
   Hipparcos rotation.  The units are radians per year (Julian,
   TDB).

Called:
   eraRv2m      r-vector to r-matrix

Reference:

   F.Mignard & M.Froeschle, Astron.Astrophys., 354, 732-739 (2000).

This revision:  2023 March 6

Copyright (C) 2013-2023, NumFOCUS Foundation.
Derived, with permission, from the SOFA library.  See notes at end of file.

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fk5hip¶