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gsn_polymarker

Draws polymarkers on the given plot.

Prototype

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

	procedure gsn_polymarker (
		wks  [1] : graphic,  
		plot [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.

plot

A plot identifier created by using one of the many gsn functions, or by calling create to create a View object.

x
y

Multi-dimensional arrays of the same length containing the X and Y coordinates of the polymarkers, and must be in the range of the X/Y coordinates of the data in plot. If drawing markers on a map, then X should correspond to longitude values, and Y to latitude values.

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 that 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.

If you want to resize the plot (i.e. by passing the plot to gsn_panel or setting the vpWidthF or vpHeightF resources), then use the function gsn_add_polymarker. This will cause the polymarkers to be attached to the given plot, and hence automatically resized when the plot is resized.

See Also

gsn_polygon, gsn_polyline, gsn_polygon_ndc, gsn_polymarker_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

Examples

For some application examples, see:

Also, see the suite of polymarker examples.