gc2gd¶

erfa.gc2gd(n, xyz)[source]¶

Transform geocentric coordinates to geodetic using the specified reference ellipsoid.

Parameters:

nint array
xyzdouble array

Returns:

elongdouble array
phidouble array
heightdouble array

Notes

Wraps ERFA function eraGc2gd. The ERFA documentation is:

- - - - - - - - -
 e r a G c 2 g d
- - - - - - - - -

Transform geocentric coordinates to geodetic using the specified
reference ellipsoid.

Given:
   n       int        ellipsoid identifier (Note 1)
   xyz     double[3]  geocentric vector (Note 2)

Returned:
   elong   double     longitude (radians, east +ve, Note 3)
   phi     double     latitude (geodetic, radians, Note 3)
   height  double     height above ellipsoid (geodetic, Notes 2,3)

Returned (function value):
          int         status:  0 = OK
                              -1 = illegal identifier (Note 3)
                              -2 = internal error (Note 3)

Notes:

1) The identifier n is a number that specifies the choice of
   reference ellipsoid.  The following are supported:

      n    ellipsoid

      1     ERFA_WGS84
      2     ERFA_GRS80
      3     ERFA_WGS72

   The n value has no significance outside the ERFA software.  For
   convenience, symbols ERFA_WGS84 etc. are defined in erfam.h.

2) The geocentric vector (xyz, given) and height (height, returned)
   are in meters.

3) An error status -1 means that the identifier n is illegal.  An
   error status -2 is theoretically impossible.  In all error cases,
   all three results are set to -1e9.

4) The inverse transformation is performed in the function eraGd2gc.

Called:
   eraEform     Earth reference ellipsoids
   eraGc2gde    geocentric to geodetic transformation, general

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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gc2gd¶