SLA_SEP

Angle Between 2 Points on Sphere

ACTION:
Angle between two points on a sphere (single precision).
CALL:
R = sla_SEP (A1, B1, A2, B2)
GIVEN:

A1,B1

R

spherical coordinates of one point (radians)

A2,B2

R

spherical coordinates of the other point (radians)


RETURNED:

sla_SEP

R

angle between [A1,B1] and [A2,B2] in radians


NOTES:
(1)
The spherical coordinates are right ascension and declination, longitude and latitude, etc. in radians.
(2)
The result is always positive.