true_angular_distance

pycraf.geometry.true_angular_distance(l1, b1, l2, b2)

True angular distance between points (l1, b1) and (l2, b2).

Based on Vincenty formula (http://en.wikipedia.org/wiki/Great-circle_distance). This was spotted in astropy source code.

Parameters:

l1, b1Quantity

Longitude/Latitude of point 1 [deg]

l2, b2Quantity

Longitude/Latitude of point 2 [deg]

Returns:

adistQuantity

True angular distance [deg]