pn

erfa.pn(p)[source]

Convert a p-vector into modulus and unit vector.

Parameters:
pdouble array
Returns:
rdouble array
udouble array

Notes

Wraps ERFA function eraPn. The ERFA documentation is:

- - - - - -
 e r a P n
- - - - - -

Convert a p-vector into modulus and unit vector.

Given:
   p        double[3]      p-vector

Returned:
   r        double         modulus
   u        double[3]      unit vector

Notes:

1) If p is null, the result is null.  Otherwise the result is a unit
   vector.

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

Called:
   eraPm        modulus of p-vector
   eraZp        zero p-vector
   eraSxp       multiply p-vector by scalar

This revision:  2021 May 11

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