  0  &lt;  lon  &lt;  2*pi
                   -

             However, round-off error could cause 'lon' to equal 2*pi.

       lat   the value(s) describing the planetographic latitude of the
             input point.

             [1,n] = size(lat); double = class(lat)

             For a point P on the reference spheroid, this is the angle
             between the XY plane and the outward normal vector at
             P. For a point P not on the reference spheroid, the
             planetographic latitud