[gradsusr] Gray scale

[Galebonwe Ramaphane]

Graduser,

I'm attempting to display cloud cover in grayscale. I would like
something like ;

25% cover        ----- very light gray
50% cover       ----- light gray
75% cover        ----gray
100% cover     ----dark gray/black
 
I have also attempted to define my RGB gray scale( see attached script).
However I seem to get only one color on the plot( see attached picture)

I defined my clevs and ccols thus;

   rgb_gray1
   set gxout shaded
  * set cmin 15
   set clevs 25 50 75 100
   set ccols 0 23 24 28 30
   display clcm
   cbarn

Any  suggestions will be welcome.

Galebonwe Ramaphane
Department of Meteorological Services
P.O. BOX 10100
Gaborone
Botswana
Tel: +267 3612200
 

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