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RGDATA

        [GREG2\]RGDATA [Name|Array_X Array_Y Array_Z] [/SUBSET  NXmin  NYmin
    NXmax  NYmax]  [/VARIABLE]  [/FORMAT  Fmt [code]] [/INCREMENT IncX IncY]
    [/BLANKING Bval]

    This command optionally creates, then loads a two-dimensional  map  into
    the  Regular  Grid array (to be contoured by RGMAP, plotted by PLOT...).
    This is THE basic command needed for subsequent 2-dimensional treatment.
    "Regular Grid" means that data is internally stored as a two-dimensional
    array, thus lies on a Regularly sampled Grid. The  user-provided  "pixel
    values"  may  come from various "descriptions" of such regularly sampled
    (but possibly uncompletely sampled) data:
       1) Three 1-dimensional arrays, say, X Y and Z, that contain  Z=f(X,Y)
        at regular intervals in X and Y.
       2) A preexisting internal 2-D array (possibly a section of a 3D or 4D
        array).
       3) An external, specially formatted, file.

    For data NOT REGULARLY ("randomly") sampled,  use  the  GREG2\RANDOM_MAP
    command  instead. The Regular Grid is itself a 2D SIC variable under the
    name "RG". Its extrema are available in the variables  RGMIN  and  RGMAX
    (values)  and  RG_XMIN,  RG_XMAX,  RG_YMIN, and RG_YMAX (position). Once
    loaded, the RG can be saved on a file with the command GREG2\WRITE.

    The following command syntax is used to deduce  which  "description"  is
    provided:

      - With  0  or 3 arguments, RGDATA will try to assemble Z=f(X,Y) either
        from the X,Y and Z arrays (as defined by  command  COLUMN)  or  from
        "Array_X Array_Y Array_Z", that should be 1D SIC variables previous-
        ly created. The option /INCREMENT is used to force the X and Y  sam-
        pling  interval  to (IncX,IncY) in case of roundoff errors. Defining
        twice the same pixel is an error. If a blanking value  is  currently
        defined,  non-sampled pixels will be attributed this value, which is
        overriden by the Bval value of the /BLANKING option. Note that, if a
        blanking  value is currently defined, pixels for which X or Y are in
        the blanking range are themselves blanked.

      - With ONE argument (Name) following the command, Name is taken as the
        name  of an existing SIC 2D variable if option /VARIABLE is present.
        Otherwise, Name  is  a  specially  formatted  file  (see  HELP RGDA-
        TA FILE_FORMAT) from which the Regular Grid array must be read in.

    A  rectangular  subset  of the array defined by the pixel coordinates of
    the Bottom Left Corner and Top Right Corner can be  selected  thanks  to
    the /SUBSET option.


Subsections

Gildas manager 2023-06-01