comdat

 COMDAT -- computes data equivalent to a particular image. This can be
           subtracted from real data to give data residuals. comdat is
           also useful for simulating data. comdat uses exactly the same
           image to data routine as optscl and memit and should therefore
           give the same chi**2 (for the same image and data). Noise can
           optionally be added.


 Parameters:

   IMAGE     -- The image file to load
   TEMPLATE  -- TRUE if template data file is to be used otherwise the user
                must define pixels sizes etc
   If TEMPLATE

     DATA      -- Data file containing example format data

   Else

     NPIX      -- Number of pixels/spectrum        
     NSPEC     -- Number of spectra
     VDATA     -- Velocity km/s/pixel
     WCEN      -- Central wavelength (Angstroms)
     WIDTH     -- Phase width of exposures

   OUTPUT    -- Calculated data file name
   NADD      -- TRUE if noise is to added to data

   If NADD

     CONT      -- Effective continuum for noise computation
     NOISE     -- Signal-to-noise in effective continuum
     SEED      -- Seed integer to start noise generator if NADD

This command belongs to the class: essential