pv2s¶
- erfa.pv2s(pv)[source]¶
Convert position/velocity from Cartesian to spherical coordinates.
- Parameters:
- pvdouble array
- Returns:
- thetadouble array
- phidouble array
- rdouble array
- tddouble array
- pddouble array
- rddouble array
Notes
Wraps ERFA function
eraPv2s
. The ERFA documentation is:- - - - - - - - e r a P v 2 s - - - - - - - - Convert position/velocity from Cartesian to spherical coordinates. Given: pv double[2][3] pv-vector Returned: theta double longitude angle (radians) phi double latitude angle (radians) r double radial distance td double rate of change of theta pd double rate of change of phi rd double rate of change of r Notes: 1) If the position part of pv is null, theta, phi, td and pd are indeterminate. This is handled by extrapolating the position through unit time by using the velocity part of pv. This moves the origin without changing the direction of the velocity component. If the position and velocity components of pv are both null, zeroes are returned for all six results. 2) If the position is a pole, theta, td and pd are indeterminate. In such cases zeroes are returned for all three. This revision: 2021 May 11 Copyright (C) 2013-2023, NumFOCUS Foundation. Derived, with permission, from the SOFA library. See notes at end of file.