; REFREQ
;---------------------------------------------------------------
;! Allows changing of reference pixel
;# PROCEDURE UV CALIBRATION
;-----------------------------------------------------------------------
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;---------------------------------------------------------------
REFREQ    LLLLLLLLLLLLUUUUUUUUUUUU CCCCCCCCCCCCCCCCCCCCCCCCCCCCC
REFREQ    Procedure to change reference frequency or pixel
INNAME                             Input UV file name (name)
INCLASS                            Input UV file name (class)
INSEQ             0.0     9999.0   Input UV file name (seq. #)
INDISK            0.0        9.0   Input UV file disk unit #
INVER                              FQ table to modify
SUBARRAY          0.0     1000.0   Subarray, 0 => 1.
PIXVAL                             Desired reference pixel
OFFSET                             Desired reference pixel shift
                                    (ignored if PIXVAL<>0)
PRTLEV                             Control amount of output when
                                   file is run.
              To run type RUN REFREQ
----------------------------------------------------------------
REFREQ
Task:  REFREQ allows you to move the reference pixels
       to other parts of the band. Please contact daip@nrao.edu
       with questions, comments, or suggestions.  REFREQ is a
       run file, to use it set the inputs then type RUN REFREQ.
Adverbs:
  INNAME.....Input UV file name (name).      Standard defaults.
  INCLASS....Input UV file name (class).     Standard defaults.
  INSEQ......Input UV file name (seq. #).    0 => highest.
  INDISK.....Disk drive # of input UV file.  0 => any.
  SUBARRAY...Subarray number to use. NO DEFAULT
  PIXVAL.....Desired reference pixel, overrides OFFSET.
  OFFSET.....Desired reference pixel shift, ignored if PIXVAL is set.
  PRTLEV.....>=0 print progress messages
             >=1 print pre and post-process FQ table
             < 0 nothing printed
----------------------------------------------------------------
REFREQ:  Geodesy experiments may benefit if the reference pixel
         is nearer the center of the frequenies sampled in the
         observation - this task lets you change the reference
         pixel
DOCUMENTOR: A. Mioduszewski
PROGRAMMER: K. Desai, NRAO/SOC

                        PURPOSE
                        -------

REFREQ allows you to consistently change the reference pixel so that
FRING solutions are referenced to near the center of the solution
interval [in time and frequency].  REFREQ does not modify the actual
frequency information contained in the tables produced by the
correlator as a record of how the correlation was performed.
