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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...).
Gildas manager
2024-04-17