EXTREMA
Keywords: greg

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EXTREMA

            [GREG2\]EXTREMA [/BLANKING Bval  Eval]  [/PLOT]  [/COMPUTE]  [/LOCAL
        PLOT|TERMINAL|FileName]

        Computes  and  shows  the minimum and maximum values of the Regular Grid
        array: shows XMIN,XMAX,YMIN,YMAX,ZMIN,ZMAX. A useful command for  decid-
        ing  where to set contour levels, or what size to give to the BOX if you
        want an exact aspect ratio between two coordinates. The current blanking
        value is used, but can be overridden using option /BLANKING.

        Option  /LOCAL  specifies that instead of computing global extrema LOCAL
        extrema values should be computed and:
          - PLOT: written at appropriate places on the plot. This is a very good
            way  to  avoid ambiguities in contour map. A shortest format is used
            for writing the values, and the character size  controls  the  label
            size. /PLOT is an alias for /LOCAL PLOT.
          - TERMINAL: written to the terminal,
          - FileName: written to the given file name.
        These  arguments  can  be combined. If output is TERMINAL and/or file, X
        and Y values are offsets in radians.

        If option /COMPUTE is not present, the global extrema are only  computed
        if  not already known (from a previous call to EXTREMA, or from an image
        header). /COMPUTE forces computation from the data array. It  should  be
        used  if  for  any reason the known extrema are incorrect (invalid image
        header, killed bad pixel, change of blanking value...).