; INTERPOL
;---------------------------------------------------------------
;! specifies the type of averaging done on the complex gains
;# ADVERB CALIBRATION
;-----------------------------------------------------------------------
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;-----------------------------------------------------------------------
INTERPOL  LLLLLLLLLLLLUUUUUUUUUUUU CCCCCCCCCCCCCCCCCCCCCCCCCCCCC
----------------------------------------------------------------
INTERPOL
Type: Adverb  (String*4)
Use:  Standard data selection adverb; used to specify the
      interpolation function to be applied to the gain table:
      In CLCAL:
         '    ' = linear vector interpolation with no SN smoothing.
         '2PT ' = linear vector interpolation with no SN smoothing.
         'SELF' = do 2PT but only using SN entries from the same
                  source.  (New mode starting 20 April 2004.)
         'SELN' = Use only SN solution from same source which is
                  closest in time.  (This mode was called SELF before
                  20 April 2004.)
         'POLY' = Fit a polynomial to the SN rates and delays.  Use
                  the integral of the rate polynomial for the phases.
         'SIMP' = Simple linear phase connection between SN phase
                  entries, assumes phase difference less than 180 deg.
         'AMBG' = Linear phase connection using rates to resolve phase
                  ambiguities.
         'CUBE' = As AMBG but fit third order polynomial to phases and
                  rates.
      This adverb is only relevant when the data being operated
      on has an associated gain table.
Null value:  '    ' see above.
Tasks:
   CLCAL......Merges and smooths SN tables, applies them to CL tables.
Procedures: pass INTERPOL to CLCAL
   VLACLCAL...Runs CLCAL and prints the results with LISTR.
   VLBAFRGP...Fringe fit phase referenced data and apply calibration.
   VLBAFRNG...Fringe fit data and apply calibration.
   VLBAKRGP...Fringe fit phase referenced data and apply calibration.
   VLBAKRNG...Fringe fit data and apply calibration.
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