Program:      irdspos

Purpose:      Extract projected sky positions from positions
              in an IRDS set.

Category:     IRAS

File:         irdspos.c

Author:       Fred Lahuis

Keywords:

   IRSET=     IRDS data set.

   POS=       Pixel position for which to return the                   [1,1,0,1]
              sky position. The pixel position should be given as 
              an array containing SAMPLE , SDET, SNIP and TICK in 
              subsequent order.
              SDET = 0 corresponds to boresight,
              SDET < 0 corresponds to the center of gravity of 
              band number SDET (see IRCC_BANDNR etc.).
              Use of one of the hidden keywords SAMPLE, TICK, SDET 
              and SNIP overwrites the corresponding value given here.

   COOR=      Coordinate system.                      [as defined in the header]
              Standard coordinate systems:
                  Equatorial
                  Galactic
                  Ecliptic
                  Supergalactic
                  Sunreferenced
   
 **PROJ=      Type of projection.                                         [NONE]
              Entering H(elp) or ? returns the projections possible.
                               
 **SAMPLE=    Array containing sequential SAMPLE points.                [pos[0]]

 **SDET=      Array containing sequential SDET points.                  [pos[2]]
              SDET = 0 corresponds to boresight,
              SDET < 0 corresponds to the center of gravity of
              band number SDET (see IRCC_BANDNR etc.)

 **SNIP=      Array containing sequential SNIP points.                  [pos[3]]

 **TICK=      Array containing sequential TICK points.                  [pos[1]]


Description: 

Comments:                  

Updates:      Juli 2 1991:     FL Document created.
              December 4 1991: FL input to COOR and PROJ changed.