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gsn_polymarker_ndc

Draws polymarkers on 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_polymarker_ndc (
		wks [1] : graphic,  
		x       : numeric,  
		y       : numeric,  
		res [1] : logical   
	)

Arguments

wks

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

x
y

Multi-dimensional arrays of the same length containing the X and Y coordinates of the polymarkers, which must be normalized device coordinates (NDC).

res

A variable containing an optional list of polymarker resources, attached as attributes. Set to True if you want the attached attributes to be applied, and False if you either don't have any resources to set, or you don't want the resources applied.

Description

If a missing value is encountered in x and/or y, then this pair is ignored, and no polymarker will be drawn at that pair.

There are many marker styles available, and you can use the gsMarkerIndex resource to change the marker style. The default is an asterisk. You can also create your own marker style using the NhlNewMarker function.

See Also

gsn_polygon, gsn_polymarker, gsn_polyline, gsn_polygon_ndc, gsn_polyline_ndc, gsn_add_polygon, gsn_add_polymarker, gsn_add_polyline, gsn_text, gsn_text_ndc, gsn_add_text, gsn_add_shapefile_polylines, gsn_add_shapefile_polymarkers, gsn_add_shapefile_polygons, NhlNewMarker, NhlNewDashPattern, drawNDCGrid

Examples

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

begin
  wks = gsn_open_wks("ncgm","gsn_polymarker_ndc")  ; Open a workstation.
 
  markx = (/ .415, .326, .225, .159, .159, .225, .326, .415, .450/)
  marky = (/ .846, .898, .880, .801, .699, .620, .602, .654, .750/)

  gsres = True              ; Indicate you want to set some resources.
  gsres@gsMarkerColor = 3   ; Change marker color.
  gsres@gsMarkerSizeF = 10. ; Increase marker size by a factor of 10.

  gsn_polymarker_ndc(wks,markx,marky,gsres)  ; Draw the polymarkers.

  gsres@gsMarkerColor = 18   ; Change marker color.
  gsres@gsMarkerIndex = 16   ; Change marker type to a filled circle.

  gsn_polymarker_ndc(wks,markx+.4,marky-.4,gsres) ; Draw the polymarkers.

  frame(wks)  ; Advance the frame.
end