;DARKLINE
;---------------------------------------------------------------
;! The level at which vectors are switched from light to dark
;# ADVERB PLOT
;-----------------------------------------------------------------------
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;;  Associated Universities, Inc. Washington DC, USA.
;;
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;-----------------------------------------------------------------------
DARKLINE  LLLLLLLLLLLLUUUUUUUUUUUU CCCCCCCCCCCCCCCCCCCCCCCCCCCCC
----------------------------------------------------------------
DARKLINE
Type:     Adverb   (Scalar)
Use:      Plot programs are able to draw "dark" as well as "bright"
          vectors.  The dark ones are normally drawn to provide
          contrast when the background grey-scale image is strong.
          DARKLINE is used to control the grey level, after scalings
          and FUNCTYPE (in the range 0 - 1) at which the switch to
          dark is made.  The default value is 0.33.
Tasks:
  GREYS.......Make a grey-scale plot with contours.
  KNTR........Make a contour/grey plot file from an image w multiple
              panels.
  PCNTR.......Make a grey-scale, contour, and polarization vector
              plot.
----------------------------------------------------------------
