; DOBLANK
;---------------------------------------------------------------
;! controls handling of blanking
;# ADVERB PLOT
;-----------------------------------------------------------------------
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;;  Associated Universities, Inc. Washington DC, USA.
;;
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;;  modify it under the terms of the GNU General Public License as
;;  published by the Free Software Foundation; either version 2 of
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;;
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;-----------------------------------------------------------------------
;---------------------------------------------------------------
DOBLANK   LLLLLLLLLLLLUUUUUUUUUUUU CCCCCCCCCCCCCCCCCCCCCCCCCCCCC
----------------------------------------------------------------
DOBLANK
Type: Adverb  (Logical,  > 0  =>  true)
Use:  To control the handling of blanking and/or blanked pixels.
      The actual meaning depends on the task (see below).
Null value:  0 false
Tasks:
   CHKFC....Makes images of Clean boxes from Boxfile.  DOBLANK > 0
            causes magic blanks to be written outside Clean boxes.
   CLCAL....Merges and smooths SN tables, applies them to CL tables.
            DOBLANK controls how blanked (failed) solutions are
            handled.
   CLSMO....Smooths a calibration CL table.  DOBLANK controls whether
            good or failed solutions are the ones changed.
   CONVL....Convolves an image with a gaussian or another image.
            DOBLANK > 0 causes the smoothed output to be blanked at
            those pixels which were blanked on input.
   ELFIT....Plots/fits selected contents of SN, TY, SY, PC or CL files.
            DOBLANK > 0 controls the plot symbol used for blanked data,
            otherwise they are omitted.
   KNTR.....Make a contour/grey plot file from an image w multiple
            panels.  DOBLANK > 0 causes the boundary between blanked and
            normal pixels to be plotted.
   MASKS....Makes mask image of Clean boxes from boxfile.  DOBLANK > 0
            cuses the pixels outside of Clean boxes to be magic blanks.
   SNBLP....Plots selected contents of SN or CL files on a baseline
            basis.  DOBLANK > 0 selects the plot symbol for blanked
            data which are otherwise omitted.
   SNFIT....Fits parabola to SN amplitudes and plots result.  DOBLANK>0
            selects the plot symbol for blanked data which are otherwise
            omitted.
   SNIFS....Plots selected contents of SN, TY, SY, PC or CL files by
            IF.  DOBLANK > 0 selects the plot symbol for blanked data
            which are otherwise omitted.
   SNPLT....Plots selected contents of SN, SY, TY, PC or CL files versus
            time.  DOBLANK > 0 selects the plot symbol for blanked data
            which are otherwise omitted.
   SNSMO....Smooths and filters a calibration SN table.  DOBLANK
            controls whther good or blanked solutions (or both) are
            changed.
   SPCOR....Task to correct an image for a primary beam and spectral
            index.  DOBLANK > 0 causes the output to be blanked where
            the spectral index image is blanked.  Else output is the
            beam corrected input with no spectral index alteration.
   SYVSN....Plots selected SY/TY data with SN solution values versus
            time.  DOBLANK > 0 controls the plt symbol used for blanked
            data which are otherwise omitted.
   TYSMO....Smooths and filters a calibration TY or SY table.  DOBLANK
            controls whether blanked or good data or both are changed.
   UVHIM....Makes image of the histogram on two user-chosen axes.
            DOBLANK > 0 causes all 0 values to be written with magic
            blanks.
----------------------------------------------------------------