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Returns a list of resources associated with the given class name and an optional filter string.

Available in version 5.2.0 and later.


	function NhlGetClassResources (
		class_name    [1] : string,  
		filter_string [1] : string   

	return_val [*] :  string



An NCL class name, like "contourPlotClass", "mapPlotClass" or "vectorFieldClass".


A filter string to further narrow down the list of resources returned. This string can be a regular expression, like "^cn", which indicates to return only strings that start with "cn". All matching is performed in a case-insensitive manner: the filter string "fillcolor" would return resource names containing this string in any combination of upper and lower case letters.

If "" is used for this string, then all resources associated with that class will be returned.

Return value

The list of matched resources is returned as an array of strings. If no matching resources are found, then a missing string value is returned.


Given a class name and a "filter" (regular expression), this function returns a list of matched resources associated with that class. Note that this function only works on classes that are "creatable" by the user, like ContourPlot, MapPlot, and pdfWorkstation. You cannot retrieve the resources for classes like PlotManager and View. See the next paragraph for more information.

The filter_string can be used to narrow the resources that are returned to those that apply to the situation at hand and can also help discover the exact spelling of a resource you may not remember exactly. Note that the full list of resources for a class includes both superclass and composite class member resources unless they have been disabled by the class. For instance, the full resource list for the ContourPlot class includes the resources of its View (vp) and Transform (tf) superclasses, as well as those of its composite Transformation (tr), PlotManager (pm), LabelBar (lb), Legend (lg), Title (ti), and TickMark (tm) class members. Disabled resources are composite class member resources over which the user has no control because they are set automatically. An example would be the lbFillColors resource, which the ContourPlot class sets for its composite class LabelBar based on the colors used in a filled contour plot.

A full description of the syntax and capabilities of regular expressions is beyond the scope of this document. See the Unix/POSIX man page for REGEX (7) or similar documentation for a complete explanation, noting that NCL's implementation uses the "modern" form of regular expressions. In reality only a very small subset of the full functionality will be needed for the purposes of this function. For those not familiar with the topic one basic point is that unlike the use in a directory listing of the asterisk ('*') as a wildcard standing for any number of arbitrary characters, the equivalent operator in a regular expression consists of the two character sequence: '.*'.

The full list of class names can be found at

See Also



Example 1:

To get a list of all resources associated with an X11 workstation:

  wk_strs = NhlGetClassResources("xWorkstationClass","")

The above returns:

  (0)     wkBackgroundColor
  (1)     wkColorMap
  (2)     wkColorMapLen
  (3)     wkDashTableLength
  (4)     wkDefGraphicStyleId
  (5)     wkFillTableLength
  (6)     wkForegroundColor
  (7)     wkGksWorkId
  (8)     wkHeight
  (9)     wkIconTitle
  (10)     wkMarkerTableLength
  (11)     wkPause
  (12)     wkTitle
  (13)     wkTopLevelViews
  (14)     wkVSWidthDevUnits
  (15)     wkViews
  (16)     wkWidth
  (17)     wkWindowId
  (18)     wkX
  (19)     wkXColorMode
  (20)     wkY

Example 2:

To get a list of all map resources that contain any form of the word "fillcolor":

  mp_strs = NhlGetClassResources("mapPlotClass","fillcolor")

The above returns:

  (0)     lbFillColor
  (1)     lbFillColors
  (2)     lbMonoFillColor
  (3)     lbPerimFillColor
  (4)     lgPerimFillColor
  (5)     mpDefaultFillColor
  (6)     mpFillColor
  (7)     mpFillColors
  (8)     mpInlandWaterFillColor
  (9)     mpLandFillColor
  (10)     mpMonoFillColor
  (11)     mpOceanFillColor
  (12)     mpSpecifiedFillColors

Example 3:

To get a list of all labelbar resources associated with a contour plot:

  lb_strs = NhlGetClassResources("contourPlotClass","^lb")

The above returns:

  (0)     lbAutoManage
  (1)     lbBottomMarginF
  (2)     lbBoxFractions
  (3)     lbBoxLineColor
  (4)     lbBoxLineDashPattern
  (7)     lbBoxLinesOn
 . . .
  (57)     lbTitleJust
  (58)     lbTitleOffsetF
  (59)     lbTitleOn
  (60)     lbTitlePosition
  (61)     lbTitleString
  (62)     lbTopMarginF

Example 3:

To get a list of all resources that belong to the actual contourPlotClass and have somthing to do with contour levels:

  level_strs = NhlGetClassResources("contourPlotClass","^cn.*level")

The above returns:

   (0)     cnLegendLevelFlags
   (1)     cnLevelCount
   (2)     cnLevelFlag
   (3)     cnLevelFlags
   (4)     cnLevelSelectionMode
   (5)     cnLevelSpacingF
   (6)     cnLevels
   (7)     cnMaxLevelCount
   (8)     cnMaxLevelValF
   (9)     cnMinLevelValF
   (10)    cnMonoLevelFlag