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gsn_streamline_scalar

Creates and draws a streamline plot colored by a given scalar field.

Available in version 5.2.0 and later.

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_scalar (
		wks     [1] : graphic,  
		u    [*][*] : numeric,  
		v    [*][*] : numeric,  
		data [*][*] : 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.

data

The data for which to color the streamlines by; 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 streamline plot created is returned. The id of the streamline data object is returned as an attribute called vfdata, and the id of the scalar data object is returned as an attribute called sfdata. This is useful if you want to use setvalues to change some data options after this function has been called.

Description

This function creates and draws a streamline plot colored by a scalar field on the given workstation.

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

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