idlastro / Astronomical Utilities: AITOFF

[Source code]

NAME
AITOFF
PURPOSE
Convert longitude, latitude to X,Y using an AITOFF projection.
EXPLANATION
This procedure can be used to create an all-sky map in Galactic 
coordinates with an equal-area Aitoff projection.  Output map 
coordinates are zero longitude centered.
CALLING SEQUENCE
AITOFF, L, B, X, Y 
INPUTS
L - longitude - scalar or vector, in degrees
B - latitude - same number of elements as L, in degrees
OUTPUTS
X - X coordinate, same number of elements as L.   X is normalized to
        be between -180 and 180
Y - Y coordinate, same number of elements as L.  Y is normalized to
        be between -90 and 90.
NOTES
See AIPS memo No. 46, page 4, for details of the algorithm.  This
version of AITOFF assumes the projection is centered at b=0 degrees.
REVISION HISTORY
Written  W.B. Landsman  STX          December 1989
Modified for Unix:
        J. Bloch        LANL SST-9      5/16/91 1.1
Converted to IDL V5.0   W. Landsman   September 1997