

               [3,1] = size(spoint); double = class(spoint)

               `spoint' need not be visible from the observer's
               location at the epoch `et'.

               The components of `spoint' have units of km.

   the call:

      [trgepc, srfvec, phase, solar, emissn, visibl, lit] = ...
                                          <b>cspice_illumf</b>( method, ...
                                          target, ilusrc, et, fixref, ...
                                          abcorr, ob