As of Mon Jul 15 19:16:32 2024

QUOUT: Task to write Q/U spectrum to text file for RLDIF


INNAME                             UV or image data (name).
INCLASS                            UV or image data (class).
INSEQ             0.0    9999.0    UV or image data (seq. #).
                                      0 => high
INDISK                             Disk unit #.       0 => any
FORMAT            0.0       4.0    = 0,1 write Q, U
                                   = 2 write polarization angle
OUTTEXT                            Output text file
SOURCES                            UV: Source list from CP/SU
INVERS                             UV: CP table version #
BLC                                MA: Bottom left corner
TRC                                MA: Top left corner


Type:  Task
Use:   RLDIF requires a spectrum of the expected polarization angle of
       the polarization calibrator as a function of frequency.  One
       way to provide those data is via a text file.  QUOUT will write
       that text file from a UV data set using the CP or SU table
       values of Q and U.  NOTE that those values must be fully
       calibrated - i.e. from a data set on which RLDIF has already
       been run.  QUOUT is then used to transfer the calibration of a
       source to another data set.

       If the input is an image "cube", then QUOUT will determine the
       output by fitting Q and U in a small window set by BLC and TRC.
       The cube may be a four-dimensional (or more) image with Q and U
       on a polarization axis or it may be an output of COMB of
       polarization angle (OPCODE 'POLA') in three or more
       dimensions.  The "Q" and "U" written from a POLA image are just
       the cos and sin of the average of twice the position angles
       rather than properly scaled fluxes.
  INNAME.....UV or image file name (name).  Standard defaults.
  INCLASS....UV or image file name (class).  Standard defaults.
  INSEQ......UV or image file name (seq. #).  0 => highest.
  INDISK.....Disk unit #.                     0 => any.
  FORMAT.....Write OUTTEXT with Freq, Q, U, source number when FORMAT
             is < 1.5.  Write it with Freq, Polarization angle, source
             number when FORMAT > 1.5.
  OUTTEXT....Outout text file.  Contents described below.
For UV input
  SOURCES....List of sources to be listed. '  '=> all.
  INVERS.....CP (calibrator polarization) table version number.  If
             < 0 or there are no CP tables, use  the SU (source)
For image data
  BLC........Bottom left corner of area over which image is
  TRC........Top right corner

OUTTEXT file format:
   1. Begins with a line which defines the contents of the file
         ;FQUS   for columns of frequency, Q, U, and source number.
         ;FAS    for columns of frequency, polarization angle, and
                 source number
   2. Comment lines at any point begin in column 1 with either a
      ; or a # character.
   3. Data lines contain the specified type of data columns:
         ;FQUS   frequency in GHz, Q, U in the same units, and
                 optionally source number
         ;FAS    frequency in GHz, polarization angle in degrees
                 (= ATAN2 (U, Q) / 2.0), and optionally source number
      The source number may be omitted or set to 0 if there is only
      one source included.

Example 1:
# QUOUT run 12-JAN-2011 11:24:35 using CP version    2
  4.988000000    0.348104    0.780174      0
  4.990000000    0.348104    0.780174      0
  4.992000000    0.346920    0.780659      0
  4.994000000    0.344028    0.781819      0
  4.996000000    0.338668    0.783813      0
  4.998000000    0.336427    0.784259      0

Example 2:
# QUOUT run 12-JAN-2011 11:27:03 using CP version    2
  4.988000000    32.97708      0
  4.990000000    32.97708      0
  4.992000000    33.01998      0
  4.994000000    33.12441      0
  4.996000000    33.31594      0
  4.998000000    33.39096      0