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gsn_csm_hov

Creates and draws a Hovmueller (time vs. longitude) 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_hov (
		wks     [1] : graphic,  
		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.

data

The two-dimensional data to contour. The rightmost dimension should be longitude.

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 contour 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 Hovmueller plot on the given workstation.

If data has a _FillValue attribute, this value will be used as a missing value.

If the resource cnFillOn is set to True, then the following will happen automatically:

  • a labelbar will be automatically added (default horizontal)
  • contour line labels will be turned off
  • the contour information label will be turned off
If you want to turn the labelbar off, set lbLabelBarOn to False.

The special resource gsnAddCyclic will be set to False so that no cyclic point will be added to the data.

If data 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 data 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.

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

See Also

gsn_contour, gsn_csm_contour, gsn_csm_time_lat, gsn_csm_lat_time, gsn_csm_pres_hgt
Special gsn resources

Examples

For some application examples, see the suite of Hovmueller plots.