pvxpv¶

erfa.pvxpv(a, b)[source]¶

Outer (=vector=cross) product of two pv-vectors.

Parameters:

adouble array
bdouble array

Returns:

axbdouble array

Notes

Wraps ERFA function eraPvxpv. The ERFA documentation is:

- - - - - - - - -
 e r a P v x p v
- - - - - - - - -

Outer (=vector=cross) product of two pv-vectors.

Given:
   a        double[2][3]      first pv-vector
   b        double[2][3]      second pv-vector

Returned:
   axb      double[2][3]      a x b

Notes:

1) If the position and velocity components of the two pv-vectors are
   ( ap, av ) and ( bp, bv ), the result, a x b, is the pair of
   vectors ( ap x bp, ap x bv + av x bp ).  The two vectors are the
   cross-product of the two p-vectors and its derivative.

2) It is permissible to re-use the same array for any of the
   arguments.

Called:
   eraCpv       copy pv-vector
   eraPxp       vector product of two p-vectors
   eraPpp       p-vector plus p-vector

This revision:  2021 May 11

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

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pvxpv¶