Cartesian coordinates to spherical coordinates (double precision).
CALL:
CALL sla_DCC2S (V, A, B)
GIVEN:
V
D(3)
vector
RETURNED:
A,B
D
spherical coordinates in radians
NOTES:
1.
The spherical coordinates are longitude (+ve anticlockwise
looking from the +ve latitude pole) and latitude. The
Cartesian coordinates are right handed, with the x-axis
at zero longitude and latitude, and the z-axis at the
+ve latitude pole.