CREATESPHERE Create a sphere containing 4 points.

   s = createSphere(p1, p2, p3, p4);
   return in s the sphere common to the 4 pointsp1, p2, p3 and p4.

   Ref: P. Bourke
   http://astronomy.swin.edu.au/~pbourke/geometry/spherefrom4/

   See also
   spheres, circles3d

   ---------
   author : David Legland 
   INRA - TPV URPOI - BIA IMASTE
   created the 22/03/2005.

Package: matgeom