ISPLANE Check if input is a plane.

   B = isPlane(PLANE) where PLANE should be a plane or multiple planes

   Example
     isPlane([...
         0 0 0 1 0 0 0 1 0;...
         0 0 0 1 0 0 -1 0 0;...
         0 0 0 1i 0 0 -1 0 0;...
         0 0 0 nan 0 0 0 1 0;...
         0 0 0 inf 0 0 0 1 0])

   See also
   createPlane3d

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 Author: oqilipo
 Created: 2017-07-09
 Copyright 2017

Package: matgeom