Purpose
Given two (x,y) pixel locations measured on an LRIS blue image,
compute the angular separation of the points and the angle
between them.
Usage
ampang x1 y1 x2 y2
Arguments
x1 = column of first position
y1 = row of first position
x2 = column of second position
y2 = row of second position
Output
The angular separation and angle (measured in various
coordinate systems) are written to stdout.
Restrictions
Exit values
0 = normal completion
1 = wrong number of arguments
Example
1) Compute the offset and direction between an object at pixel
100,100) and another at (200,200)
punaluu{lris}89
Normal coordinate system (0 deg to right, 90 deg up)
Amplitude = 30.2642 arcsec
Angle = 45 deg
Astronomical coordinate system (0 deg up, 90 deg to left)
Amplitude = 30.2642 arcsec
Angle = 315 deg