WCSARROWS
Name
wcsarrows
Purpose (one Line Only)
Draw sky-plane orientation arrows on an image based on WCS information
Description
Category
Astronomy
Calling Sequence
wcsarrows,info
Inputs
info - anonymous structure that carries the astrometric information.
You can provide a structure returned from the Astron library
(extast) or from my library (astinfo).
Optional Input Parameters
Keyword Input Parameters
X - x location of vertex of drawn arrows (default=upper right) DEVICE COORDS
Y - y location of vertex of drawn arrows (default=upper right) DEVICE COORDS
PA - position angle of one extra vector to draw, typically this is for
denoting the projected north pole vector. This angle is given in
degrees east of north. The default is to not draw this vector.
LABEL - label for the extra vector, ignored if PA not specified.
default = 'Np'
Outputs
All output is in the form of plotted information on the current window
Keyword Output Parameters
AINFO - anonymous structure that contains information computed here
x: device coordinate of center of compass
y: device coordinate of center of compass
north: angle for North vector, in degrees (0 is to the right)
east: angle for East vector, in degrees
pang: angle for extra vector, if not provided this is the
the same as north.
Common Blocks
Side Effects
Restrictions
Procedure
Modification History
2015/10/07, Written by Marc W. Buie, Southwest Research Institute