pvdpv¶

erfa.pvdpv(a, b)[source]¶

Inner (=scalar=dot) product of two pv-vectors.

Parameters:

adouble array
bdouble array

Returns:

adbdouble array

Notes

Wraps ERFA function eraPvdpv. The ERFA documentation is:

- - - - - - - - -
 e r a P v d p v
- - - - - - - - -

Inner (=scalar=dot) product of two pv-vectors.

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

Returned:
   adb      double[2]         a . b (see note)

Note:

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

Called:
   eraPdp       scalar product of two p-vectors

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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pvdpv¶