This function provides a device-independent way to ask for commonly-used
  symbols (e.g., less than or equal to, Angstrom, degree symbol, etc.),
  including all 24 Greek symbols in upper and lower case, to display with text.
  For this program to work correctly on your graphics display, you should be using
  Hershey fonts (!P.Font=-1). It will work correctly in PostScript with either
  hardware fonts (!P.Font=0) or True-Type fonts (!P.Font=1).
 
  `Greek Symbols <http://www.idlcoyote.com/ps_tips/greeksym.html>` are created by
  calling the Coyote Library routine `Greek <http://www.idlcoyote.com/programs/greek.pro>'
  from this program.

Categories

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    Graphics
   

Returns

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    A string variable that represents the requested symbol and can be used
    in a textual context.
   

Examples

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    To create a lowercase Greek psi symbol::
 
        IDL> cgPlot, findgen(11), XTitle='This title contains ' + $
                cgSymbol('psi') + ' as a Greek letter'
    To create an Angstrom sign::
 
        IDL> cgPlot, findgen(11), XTitle='This title contains (' + $
                cgSymbol('Angstrom') + ') an Angstrom sign.'
     

Author

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      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

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    Change History::
        Written by: David W. Fanning, 2 September 2011.
        Added plus-minus symbol. 2 Nov 2011. DWF.

Copyright

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    Copyright (c) 2011, Fanning Software Consulting, Inc.