CGDEMODATA 
  
   The purpose of this function is to read a selection of standard 
  
   data sets that are found in the normal IDL distribution in the 
  
   subdirectory $IDL_DIR/examples/data. At least 25 data sets are 
  
   available in all categories of data. The user selects one of the
      possible data sets with the mouse. Several of the data sets 
  
   simply create data used to illustrate graphics commands (numbers 1-3), 
  
   and two of the data sets produce random data. Data set 17 produces 
  
   a random vector of 101 elements. Data set 18 produces a 2D array of 
      random values, suitable for display as a contour plot or image.
Categories
         Utilities
          Examples
             To load the world elevation data set::
                      image = cgDemoData(7)
               Author
             FANNING SOFTWARE CONSULTING::
                      David W. Fanning 
                      1645 Sheely Drive
                      Fort Collins, CO 80526 USA
                      Phone: 970-221-0438
                      E-mail: david@idlcoyote.com
          
           Coyote's Guide to IDL Programming: http://www.idlcoyote.com
History
          Change History::
              Written by:  David W. Fanning, 5 March 1999.
      
       Added some additonal random data capability. 29 April 99. DWF
              Added IMAGES keyword. 31 March 2000. DWF.
      
       Fixed a problem with the CANCEL button. 25 Oct 2002. DWF.
      
       Added new JPEG, DICOM, TIFF, and PGN images. 30 Oct 2002. DWF.
      
       Modified old program units to work with IDL strict arrays. 29 June 2003. DWF
      
       Yikes! Somehow lost the event handler for the CANCEL button! Fixed. 1 Jan 2012. DWF.
Copyright
    
     Copyright (c) 2011-2012, Fanning Software Consulting, Inc.