[ncl-talk] Plot significant difference only (shaded color map)

[S Br]

Hello NCL,
I am plotting the difference between two files as per the script written
below, but I want to display (contour shade) only the value that are
significance at 95% level. I am able to stripe the significance difference
but can't display the difference that are significant (I want to retain the
original color shade of the difference)

diffposglob1 = avgposglobst1-avgstctrl
probtposglob1 = 100.*(1.
-ttest(avgposglobst1,varposglobst1,50,avgstctrl,varctrl,50,True,False)) ;
all areas whose value > 95 are significant

wks = gsn_open_wks("x11","surtemp_sig_diff")
 res                     = True
  res at gsnDraw             = False            ; don't draw
  res at gsnFrame            = False            ; don't advance frame
  res at cnFillOn            = False            ; turn on color
  res at cnLinesOn           = True            ; turns off contour lines.
  res at cnLineLabelsOn      = False            ; turn off line labels
  res at cnFillPalette       = "temp_diff_18lev"   ; set color map
  res at cnInfoLabelOn       = False           ; turn off cn info label
explanation
  res at lbLabelBarOn        = True           ; turn off individual cb's
  res at cnLevelSelectionMode =  "ManualLevels"
   res at cnMinLevelValF       = -1.5
   res at cnMaxLevelValF       =  1.5
   res at cnLevelSpacingF      =  0.3
   res at tmXBLabelFontHeightF = 0.030                 ; resize tick labels
   res at tmYLLabelFontHeightF = 0.030
   res at gsnStringFontHeightF = 0.030
;***********************************************************
  res2 = True                            ; res2 probability plots
  res2 at gsnDraw             = False       ; Do not draw plot
  res2 at gsnFrame            = False       ; Do not advance frome
  res2 at cnInfoLabelOn       = False
  res2 at cnLinesOn           = False       ; do not draw contour lines
  res2 at cnLineLabelsOn      = False       ; do not draw contour labels
  res2 at cnFillScaleF        = 0.3         ; add extra density
;  sgres at cnFillDotSizeF       = 0.003
  res2 at cnLevelSelectionMode = "ExplicitLevels"       ; set explicit cnlev
  res2 at cnLevels   = (/95./)              ; only have 1 contour level
  res2 at gsnRightString            = ""                ; Turn off subtitles
  res2 at gsnLeftString             = ""
  res at gsnAddCyclic                = True            ; add cyclic point
;***********************************************************
  opt = True                                         ; set up parameters
for pattern fill
  opt at gsnShadeFillType = "pattern"                   ; specify pattern fill
  opt at gsnShadeHigh      = 15                        ; stipple pattern
;  opt at gsnShadeFillScaleF = 5
;  opt at gsnShadeDotSizeF = 1                           ; make dots larger
;***********************************************************
plot = gsn_csm_contour_map(wks,diffposglob1(0,:,:),res)
  plot2   = gsn_csm_contour(wks,probtposglob1(0,:,:),res2)
  plot2   = gsn_contour_shade(plot2,-999,95., opt)      ; stipple all areas
>= 95  contour
  overlay (plot, plot2)
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mailman.ucar.edu/pipermail/ncl-talk/attachments/20190731/4c46cdec/attachment.html>