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setColorContourClear

Sets the color contours between two given levels to transparent.

Prototype

load "$NCARG_ROOT/lib/ncarg/nclscripts/csm/gsn_code.ncl"
load "$NCARG_ROOT/lib/ncarg/nclscripts/csm/gsn_csm.ncl"
load "$NCARG_ROOT/lib/ncarg/nclscripts/csm/contributed.ncl"
load "$NCARG_ROOT/lib/ncarg/nclscripts/csm/shea_util.ncl"

	function setColorContourClear (
		plot   : graphic,  
		clow   : numeric,  
		chigh  : numeric   
	)

	return_val [1] :  graphic

Arguments

plot

The plot to be modified.

clow

The low value of the range of contours that the user wishes to set to transparent.

chigh

The high value of the range of contours that the user wishes to set to transparent.

Return value

plot will be returned with the given color contours modified.

Description

This function sets contours in the range clow to chigh to clear (transparent).

Examples

load "$NCARG_ROOT/lib/ncarg/nclscripts/csm/gsn_code.ncl" 
load "$NCARG_ROOT/lib/ncarg/nclscripts/csm/gsn_csm.ncl" 
load "$NCARG_ROOT/lib/ncarg/nclscripts/csm/contributed.ncl"
load "$NCARG_ROOT/lib/ncarg/nclscripts/csm/shea_util.ncl"

begin
  f      = addfile ("/cgd/cas/shea/MURPHYS/ATMOS/80.nc", "r")
  x      = f->U(0,17,:,:)       ;Grab first timestep, 17th sigma level

  wks = gsn_open_wks("ps","test")
  res                     = True
  res@gsnDraw = False
  res@gsnFrame = False
  plot = gsn_csm_contour_map_ce(wks,x,res)    
  plot = setColorContourClear(plot,-5.,5.)      ;set all contours between -5 and 5 m/s to transparent
  draw(plot)
  frame(wks)
end