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NhlIsAllocatedColor

Queries a list of workstations to determine whether or not the given color indexes have been allocated.

Prototype

	function NhlIsAllocatedColor (
		workstations [*] : graphic,  
		color_index  [*] : integer   
	)

	return_val [dimsizes(workstations)][dimsizes(color_index)] :  logical

Arguments

workstations

An array of NCL Workstation identifiers. The identifiers are ones returned either from calling gsn_open_wks or calling create to create a Workstation object.

color_index

An array of one or more color indexes. The valid range is 0-255.

Return value

The return array is dimensioned nwks x nci , where nwks is the length of workstations, and nci is the length of the color_index.

Description

Each workstation in workstations is queried to see whether each of the elements of color_index is an allocated color or not. If an element of color_index is a missing value, then the corresponding output value is a missing value.

See Also

NhlFreeColor, NhlSetColor, NhlNewColor, NhlGetNamedColorIndex

Examples

Example 1

In the example below, two workstations are created with different colormaps, so you can see the effect of NhlIsAllocatedColor. The first (default) colormap has 32 entries, and the second (rainbow) colormap has 190 entries.

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

begin
  type = "x11"
  wks1 = gsn_open_wks(type,"example1")     ; Open a workstation with the
                                           ; default color map.
  type@wkColorMap = "rainbow"
  wks2 = gsn_open_wks(type,"example2")     ; Open a workstation with a
                                           ; different color map.
  frame(wks1)
  frame(wks2)

  is_color = NhlIsAllocatedColor((/wks1,wks2/),(/5,31,32,100,189,190,200/)) 

  do i=0,dimsizes(indexes)-1
    print("color index " + indexes(i) + ", wks1 : " + is_color(0,i) + " wks2 : " + is_color(1,i))
  end do
end

The output values should be:

(0)     color index 5, wks1 : True wks2 : True
(0)     color index 31, wks1 : True wks2 : True
(0)     color index 32, wks1 : False wks2 : True
(0)     color index 100, wks1 : False wks2 : True
(0)     color index 189, wks1 : False wks2 : True
(0)     color index 190, wks1 : False wks2 : False
(0)     color index 200, wks1 : False wks2 : False