SPECTRUM

        [DISPLAY\]SPECTRUM OutSpec InCube [Mask]
          [/CORNER Imin Imax Jmin Jmax] [/PLANE First Last]  /MEAN  or  /SUM

    Compute a Spectrum, stored in variable  OutSpec  from  an  input  data  cube
    stored  in variable InCube, by summing (if /SUM is present) or averaging (if
    /MEAN is present). OutSpec must be an existing Real array of size  equal  to
    the number of selected channels.

    The  2-D  region overwhich the summation runs is determined by the following
    rules:
      - the mask contained in variable MaskName if specified
      - the region enclosed by the current GreG polygon is any
      - the whole 2-D region otherwise
    The region is further restricted by the corners specified by option /CORNER.