[ncl-talk] Can i set the opacity of each color ??

[Rabah Hachelaf]

Hi all ,

I am using the script below to plot humidity between 40-70%(green) and
70-100% (orange).

I want to know if i can set the opacity for each color for example opacity
50% for the green color and 100% for the orange.

Thanks for help.

;************************************************
load "$NCARG_ROOT/lib/ncarg/nclscripts/csm/gsn_code.ncl"
load "$NCARG_ROOT/lib/ncarg/nclscripts/csm/gsn_csm.ncl"
load "$NCARG_ROOT/lib/ncarg/nclscripts/csm/contributed.ncl"
;************************************************
begin
 a = addfile("gfs.t00z.pgrb2f00.grib2","r")
    lon = a->lon_0
    lat = a->lat_0
    icing     = short2flt(a->RH_P0_L100_GLL0({50000},:,:))

print(icing(1:4,1:4))
;********************************************************
;  Display parameters
;***************************************
zoom="test"
pixel=2048
;***************************************************

wks_type="png"

  wks_type at wkWidth = pixel
   wks_type at wkHeight = pixel
  wks_type at wkBackgroundOpacityF = 0.0
wks = gsn_open_wks(wks_type,"icing_test")

colors = (/ (/255,255,255/),(/0,0,0/),(/255,255,255/), (/244,255,244/), \
              (/217,255,217/), (/163,255,163/), (/106,255,106/), \
              (/43,255,106/), (/0,224,0/), (/0,134,0/),(/255,145,0/),\
              (/255,178,102/) /) * 1.0 ; we multiply by 1 to make colors
float

colors = colors/255.


gsn_define_colormap(wks,colors)


res                   = True
  res at mpProjection      = "Mercator"       ; choose projection
  res at mpGridAndLimbOn   = False             ; turn on lat/lon lines
  res at mpPerimOn         = False             ; turn off box around plot
  res at mpFillOn          = False
  res at mpOutlineOn       = True
  res at cnFillOn          = True              ; color plot desired
  res at cnLineLabelsOn    = False             ; turn off contour lines
   res at mpLimitMode  = "LatLon"
   res at mpMinLatF            =   -85.0
    res at mpMaxLatF            =  85.0
    res at mpMinLonF            = -180
    res at mpMaxLonF            = 180
  res at vpXF            = 0                 ; make plot bigger
  res at vpYF            = 1
  res at vpWidthF        = 1
  res at vpHeightF       = 1

res at cnLevelSelectionMode = "ExplicitLevels"    ; set explicit contour levels
res at cnLevels    = (/ 40,70,100/) ; set levels
res at cnFillColors = (/ -1,5,11/)

;res at cnFillOpacityF=0.5

contour0 = gsn_csm_contour_map(wks,icing,res)  ; create the plot
-- 
------------------------------
Cordialement,
Best regards,
Rabah Hachelaf






-- 
------------------------------
Cordialement,
Best regards,
Rabah Hachelaf
-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://mailman.ucar.edu/pipermail/ncl-talk/attachments/20140828/2b59122a/attachment.html