; LEVS
;---------------------------------------------------------------
;! list of multiples of the basic level to be contoured
;# ADVERB PLOT
;-----------------------------------------------------------------------
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;-----------------------------------------------------------------------
;---------------------------------------------------------------
LEVS      LLLLLLLLLLLLUUUUUUUUUUUU CCCCCCCCCCCCCCCCCCCCCCCCCCCCC
----------------------------------------------------------------
LEVS
Type: Adverb  (Real array * 30)
Use:  LEVS is an array of up to 30 numbers which represent
      contour intervals.  The contour spacing is determined by
      PLEV (as a percentage of the peak intensity in an image)
      or by CLEV (as an intensity).  The elements in LEVS must
      be in ascending order since the first element smaller
      than the preceding element is the indication of the end
      of the array.  NOTE: the LEVS values do not have to be
      integers, but they will be displayed to an accuracy of
      5 digits (plus .) with 0, 1, 2, or 3 after the decimal
      depending on the value of LEVS.
Null Value: 0 * 30
      Null value assignment is -10,-9,-8,-7,-6,-5,-4,-3,-2,-1,
      1,2,3,4,5,6,7,8,9,10, 10*0.  It is most useful with the
      PLEV (Null assignment) of 10.

      The procedures below take LEVS as an input (or set LEVS to -10,-9,
      ...-1,1,2,...10) and then set colors in RGBLEVS to match these
      levels with various coloring schemes.
Procedures:
   CIRCLEVS......Sets RGBLEVS to fill LEVS with a circular color scheme.
   FLAMLEVS......Sets RGBLEVS to fill LEVS with a red flame color scheme.
   RAINLEVS......Sets RGBLEVS to fill LEVS with a rainbow color scheme.
   STEPLEVS......Sets RGBLEVS to fill LEVS with a repeated sequence of
                 colors.
Tasks:
   CCNTR.........Generate a contour plot file from an image with CC or MF
                 plotted.
   CNTR..........Generate a contour plot file or TV plot from an image.
   GREYS.........Plots images as contours over multi-level grey.
   KNTR..........Make a contour/grey plot file from an image w multiple
                 panels.
   PCNTR.........Generate plot file with contours plus polarization
                 vectors.
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