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gsn_draw_colormap

Draws the current color map for the given workstation.

Prototype

load "$NCARG_ROOT/lib/ncarg/nclscripts/csm/gsn_code.ncl"  ; This library is automatically loaded
                                                          ; from NCL V6.2.0 onward.
                                                          ; No need for user to explicitly load.

	procedure gsn_draw_colormap (
		wks [1] : graphic   
	)

Arguments

wks

A Workstation identifier. The identifier is one returned either from calling gsn_open_wks or calling create to create a Workstation object.

Description

This procedure draws the color map for the given workstation (mostly for reference and debugging purposes). The colors are draw as filled boxes labeled with the corresponding index value.

For a more flexible procedure for drawing colors and color maps, see read_color_palette. This procedure allows you to draw a set of colors or a color map without first having to set them using gsn_define_colormap.

There are some differences between gsn_define_colormap and draw_color_palette:

gsn_define_colormap draw_color_palette
The background / foreground colors are included The background / foreground colors are not included
Colors are drawn top-to-bottom, left to right Colors are drawn left to right, top-to-bottom
The filled boxes are the same size no matter how many colors you have The filled boxes are sized to fill up the frame
There are no options you can set to control how the colors are drawn There are options you can set to control how the colors are drawn (for example, to remove the number labels, to draw colors vertically instead of horizontally, etc)

See Also

draw_color_palette, gsn_define_colormap, gsn_reverse_colormap, gsn_retrieve_colormap, gsn_merge_colormaps, gsn_draw_named_colors

Examples

Example 1 (newer way)

Draw the MPL_Paired color map, and then reverse it and draw it again.

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

  wks = gsn_open_wks("x11","color")

  draw_color_palette(wks,"MPL_Paired",False)

  cmap = read_colormap_file("MPL_Paired")   ; read the color map
  draw_color_palette(wks,cmap(::-1,:),False)      ; draw the reversed color map

Example 1 (older way)

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

  wks = gsn_open_wks("x11","color")

  gsn_define_colormap(wks,"MPL_Paired")
  gsn_draw_colormap(wks)              ; Draw the color map.
  gsn_reverse_colormap(wks)           ; Reverse the color map.
  gsn_draw_colormap(wks)              ; Draw the new color map.

See also the suite of color and color map examples.