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gsn_streamline_map

Creates and draws a streamline plot over a map.

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.

	function gsn_streamline_map (
		wks  [1] : graphic,  
		u [*][*] : numeric,  
		v [*][*] : numeric,  
		res  [1] : logical   
	)

	return_val [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.

u
v

The u and v data for the streamline plot; must be two-dimensional.

res

A variable containing an optional list of plot 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.

Return value

A scalar id of the map created is returned. The id of the streamline plot is returned as an attribute called streamline, and the id of the data is returned as an attribute called data. This is useful if you want to use setvalues to change some data or streamline options after this function has been called.

Description

This function creates and draws a streamline plot over a map on the given workstation.

If either u or v have a _FillValue attribute, these values will be used as missing values.

You should use gsn_csm_streamline_map if you want a more customized streamline plot and/or if your data has coordinate arrays.

To maximize the area that the plot is drawn in, set the special resource gsnMaximize to True.

In NCL V6.1.0, this function was updated to automatically create a labelbar if stMonoLineColor is set to False.

Examples