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gsn_polyline_ndc

Draws a polyline 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_polyline_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 polyline, which must be normalized device coordinates (NDC).

res

A variable containing an optional list of polyline 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 the polyline will be disconnected at this pair.

There are many line dash patterns available, and you can use the gsLineDashPattern resource to change the dash pattern. The default is a solid line. You can also create your own dash pattern using the NhlNewDashPattern function.

See Also

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

Examples

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

begin
  npts = 500
  ii   = ispan(0,npts-1,1)
  x = 500.+.9*ii*cos(0.031415926535898*ii)
  y = 500.+.9*ii*sin(0.031415926535898*ii)

  xrange = max(x)-min(x)
  yrange = max(y)-min(y)
  y      = (y - min(y))/yrange      ; normalize x and y
  x      = (x - min(x))/xrange

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

  gsres             = True
  gsres@gsLineColor = "blue"
  gsn_polyline_ndc(wks,x,y,gsres)
  frame(wks)
end