Creating Titles on Multiple Plot Pages

QUESTION: I am using !P.MULTI to set up six plots on my page in a three-column by two-row arrangement. I want to put a title on this page, but I can't figure out how to leave room for it. How can I do it?

ANSWER: The outside margins of a multiple-plot page are controlled by the ![XYZ].OMARGIN system variables. These system variables use that old favorite of mine, character units, as the unit of measure. The default value for the outside margin is always [0,0].

Try something like this:

   !Y.OMargin = [2, 6]
   !P.Multi = [0, 3, 2]
   FOR j=0, 5 DO Plot, Findgen(11)
   XYOuts, 0.5, 0.95, ALIGNMENT=0.5, CHARSIZE=1.25, /NORMAL, $
      'This is the plot title'
   !P.Multi = 0
   !Y.OMargin = [0, 0]

The results are shown in the figure below.

Setting the outside margin of multi-plots.

 

Note that the behavior of the outside margin system variables is slightly different when outputting to PostScript files. There, you must set the !P.Multi and !Y.OMargin system variables before each page of PostScript output. If you try to do multiple page PostScript output as in the example above, the outside margins will apply only to the first page of output.

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