; PVPLOT
;---------------------------------------------------------------
;! selects a display of a polarization vector in a box in a corner
;# ADVERB PLOT
;-----------------------------------------------------------------------
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;;  Associated Universities, Inc. Washington DC, USA.
;;
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;;  published by the Free Software Foundation; either version 2 of
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;;
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;;  GNU General Public License for more details.
;;
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;-----------------------------------------------------------------------
PVPLOT    LLLLLLLLLLLLUUUUUUUUUUUU CCCCCCCCCCCCCCCCCCCCCCCCCCCCC
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PVPLOT
Type:  Adverb  (Scalar)
Use:   Used by plot tasks to control whether and where a polarization
       vector will be plotted.  The usual values mean
                  0: no vector plot
                  1: lower left corner
                  2: lower right corner
                  3: upper right corner
                  4: upper left corner
                  5: plots the VECTOR in a separate pane (KNTR)
       Grey scales, contours, and polarization vectors are not
       drawn in the vector scale box.  Plots are labeled with the
       flux that corresponds to the vector drawn.
Null value:  0 -> no vector scale plot
Tasks:
   KNTR.....Make a contour and/or grey-scale plot file from one
            or two images with multiple panels possible.  Polarization
            vectors may be plotted.
   PCNTR....Make a contour and/or grey-scale plot with polarization
            vectors.  Muti-channel contours may be overlayed in
            different colors.
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