NhlIsDataSpec

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

Prototype

	function NhlIsDataSpec (
		objects  : graphic   
	)

	return_val [dimsizes(objects)] :  logical

Arguments

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.

Description

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

DataSpec objects are objects that are created internally whenever an XY plot is created.

When you use one of the gsn XY plotting functions, like gsn_xy or gsn_csm_y, the DataSpec object that is created internally is returned as an attribute of the return variable called "dataspec".

See Also

NhlIsApp, NhlIsDataItem, NhlIsDataComm, NhlIsTransform, NhlIsView, NhlIsWorkstation

Examples

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.

load "$NCARG_ROOT/lib/ncarg/nclscripts/csm/gsn_code.ncl"

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

;
; Create a data object.
;
  npts = 500
  x    = fspan(0,npts-1,npts)
  y    = 500.+ 0.9 * x * sin(0.031415926535898*x)
  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(NhlIsDataSpec((/xy,xy@data,xy@dataspec,map,text/)))   ; Should be (/False,False,True,False,False/)