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Returns True for each given object that is a DataComm object.


	function NhlIsDataComm (
		objects  : graphic   

	return_val [dimsizes(objects)] :  logical



An array of one or more instances of NCL objects. NCL objects are created by using one of the many gsn functions, or by calling the NCL create language construct.

Return value

This function returns a logical array with the same dimensions as the input argument objects.


For each object identifier in the objects array, the value True is returned if the object is a DataComm object, and False otherwise. If any of the input values is an invalid object, then a missing value is returned for that element.

DataComm objects are objects that accept, manage, and display data, like contour plots, vector plots, and streamline plots. A map plot would not be considered a DataComm object.

See Also

NhlIsApp, NhlIsDataItem, NhlIsDataSpec, NhlIsTransform, NhlIsView, NhlIsWorkstation


Example 1

This example creates various NCL objects using both gsn functions, and by calling the NCL create language construct to create a text string.


; Create workstation.
  wks = gsn_open_wks("x11","test")

; Create a data object.
  npts = 500
  x    = fspan(0,npts-1,npts)
  xy   = gsn_xy(wks,x,y,False)

; Use the "create" construct to create a text string.
 text = create "text1" textItemClass wks
    "txString"      : "This is a string"
    "txPosYF"       : 0.5
    "txPosYF"       : 0.9
  end create

  map = gsn_map(wks,"LambertConformal",False)

  print(NhlIsDataComm((/wks,xy,map,text/)))   ; Should be (/False,True,False,False/)