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gsn_csm_vector

Creates and draws a vector plot.

Prototype

load "$NCARG_ROOT/lib/ncarg/nclscripts/csm/gsn_code.ncl"  ; These two libraries are automatically
load "$NCARG_ROOT/lib/ncarg/nclscripts/csm/gsn_csm.ncl"   ; loaded from NCL V6.2.0 onward.
                                                          ; No need for user to explicitly load.

	function gsn_csm_vector (
		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 vector 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 vector plot created is returned. The id of the data object is also returned as an attribute called data. 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 vector plot on the given workstation.

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

If the resource vcMonoLineArrowColor is set to False, then a labelbar is created. If you want to turn this labelbar off, set lbLabelBarOn to False.

If u has an attribute called "long_name", and gsnLeftString hasn't explicitly been set, then the value of this attribute is used for the left string title.

If u has an attribute called "units", and gsnRightString hasn't explicitly been set, then the value of this attribute is used for the right string title.

If your X and Y coordinate arrays have different units, then your vectors may not be drawn correctly. You may want to try setting vcMapDirection to False in this case.

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

Examples

For some application examples, see: