Welcome to the Harris Geospatial product documentation center. Here you will find reference guides, help documents, and product libraries.


  >  Docs Center  >  Libraries  >  ASTROLIB  >  GAL_FLAT

GAL_FLAT

GAL_FLAT

Name


GAL_FLAT

Purpose


Transforms the image of a galaxy so that the galaxy appears face-on

Explanation


Either a nearest-neighbor approximations or a bilinear interpolation
may be used.

Calling Sequence


RESULT = GAL_FLAT( image, ang, inc, [, cen, /INTERP ] )

Inputs


IMAGE - Image to be transformed
ANG - Angle of major axis, counterclockwise from Y-axis, degrees
For an image in standard orientation (North up, East left)
this is the Position Angle
INC - Angle of inclination of galaxy, degrees

Optional Inputs


CEN - Two element vector giving the X and Y position of galaxy center
If not supplied, then the galaxy center is assumed to coincide
with the image center

Input Keywords


INTERP - If present, and non-zero, then bilinear interpolation will be
performed. Otherwise a nearest neighbor approximation is used.

Outputs


RESULT - the transformed image, same dimensions and type as IMAGE

Method


A set of 4 equal spaced control points are corrected for inclination
using the procedure POLYWARP. These control points are used by
POLY_2D to correct the whole image.

Revision History


Written by R. S. Hill, SASC Technologies Inc., 4 December 1985
Code cleaned up a bit W. Landsman December 1992
Converted to IDL V5.0 W. Landsman September 1997



© 2018 Harris Geospatial Solutions, Inc. |  Legal
My Account    |    Store    |    Contact Us