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


EXTAST3

EXTAST3

Purpose


  This program is a wrapper procedure to the extast routine in the
  IDL astronomy user's library. extast3 is designed to handle
  data cubes, which extast cannot handle. This procedure is used by
  sky2pix to convert between sky and pixel coordinates in data cubes.

Category


  Astrometry

Calling Sequence


  extast3, hdr, result, [/delete]

Inputs


  hdr: A string array, containing a fits header. The header must
  describe a 2 or 3 dimensional fits file. If the fits file is 3D,
  all information related to 2d position on the sky must be contained
  within the first 2 dimensions of the fits file (in otherwords, the
  fits axes cannot be rotated such that spatial information lies
  along the third axis. This would be pretty non-standard, however).

Outputs


  result: A structure containing the following fields:
    extast: A pointer to the result of calling extast on hdr. If hdr
    describes a data cube, extast is 'tricked' into thinking hdr
    actually describes a 2d images. Extast contains all of the 2D sky
    astrometry data.
    cdelt3
    crpix3
    crval3

Keyword Parameters


  delete: Since result contains a pointer, these should be properly
  de-allocated at the end of use. Set the delete keyword to free the
  extast pointer and delete the result variable

See Also


  sky2pix

Modification History


  June 2009: Written by Chris Beaumont
  March 2010: Added input checking. cnb.



© 2017 Exelis Visual Information Solutions, Inc. |  Legal
My Account    |    Buy    |    Contact Us