source files: xvol.[ch]
(XVOL-FILL-HISTOGRAM :VOXELS <grl:voxels> [ :BIN-SIZE <fix:bin-size> ] [ :MIN <fix:min> ] [ :MAX <fix:max> ] [ :RESULT-IN <grl:point-y> ] )
VOXELS should be either a rank-three CLASS-16-BIT-FLOAT-ARRAY or else a graphic relation holding such an array, named :DENSITY.
'min', 'max' specify the range of pixel values which should be histogrammed.
If :BIN-SIZE is specified, it is the number of pixel values to lump together into one bin: The default value of 16 results in 256 bins. Currently, the only supported values are 1, 2, 4, 8, 16, 32, 64.
If :RESULT-IN is supplied,
point-y should be
either a CLASS-FLOAT-ARRAY at least long enough to hold
the result values, or else a graphic relation holding such
an array, named :POINT-Y. If so, the result values
will be placed in the array, and
Otherwise, a fresh relation will be allocated and the result
returned in it.