AIPS HELP file for DCHANSEL in 31DEC25

As of Mon Mar 24 13:47:00 2025

HELP SECTION

DCHANSEL
Type: Adverb  (REAL, 4 elements x 20 rows)
Use:  Data selection adverb used to specify a list of start and stop
      channel numbers plus an increment AND IF NUMBER to be used in
      some way to exclude a region of data.  Up to 20 sets of channel
      numbers/IFs can be specified.  The first two elements specify
      the start and stop channel numbers, the third specifies the
      increment within that range, i.e.if dCHANSEL = 10,20,2 that
      means take every other channel in the range 10 - 20, so that
      channels 10,12,14,16,18,20 would be excluded from the average or
      flagging or other operation.  The fourth element specifies the
      IF to which the previous three apply.
Null Value:  0
      A completely null value means no exclusions at all.
         DCHANSEL(1,i) <= 0  =>  1
         DCHANSEL(2,i) <= 0  =>  (i >= 1) -> no more channel sets
         DCHANSEL(3,i) <= 0  =>  1
         DCHANSEL(4,i) <= 0  =>  all IFs
Tasks:
  RFLAG.....Plots histograms of time rms and deviation from robust
            spectral mean/rms or flags UV data based on these.
            DCHANSEL selects regions of channels which are not
            examined at all in the plotting and flagging process.  Use
            it to omit known regions of strong (real) spectral-line
            signal.

EXPLAIN SECTION