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       COMMAND

       aaaarrrreeeeaaaa ---- ccccoooommmmppppuuuutttteeee ssssuuuurrrrffffaaaacccceeee aaaarrrreeeeaaaa ooooffff iiiimmmmaaaaggggeeee

       UUUUSSSSAAAAGGGGEEEE

       aaaarrrreeeeaaaa

       DESCRIPTION

       You may use the aaaarrrreeeeaaaa command to obtain a value for the
       developed surface area within the window defined by the
       current latitude and longitude ranges.  The aaaarrrreeeeaaaa command
       works on either cylindrical or cartesian image data.

       A single line of the following form is printed on the
       screen:

       ssssuuuurrrrffffaaaacccceeee aaaarrrreeeeaaaa ====3333222211110000....99998888ssssqqqq----ccccmmmm ssssaaaammmmpppplllleeeessss ====111133330000222211111111 vvvvooooiiiiddddssss ====888866661111

       The computation of surface area takes into account the
       possibility that some surfaces for which area measurements
       are of interest may possess significant subregions which are
       void.  The number of samples displayed by aaaarrrreeeeaaaa is the number
       of data points which are part of the contiguous surface and
       therefore contribute to the area determination.  The number
       of voids is the complement of the number of samples with
       respect to the total number of data points included in the
       current latitude and longitude range window.

       CAVEATS

       The computational algorithm for this command requires one
       latitude of data beyond the range of latitudes for which the
       developed surface area is actually calculated.  You must
       bear this in mind when citing the axial extent of the image
       corresponding to the value returned by this command.  Please
       contact the factory for an update if you need this command
       to be more accurate and robust.




















