EDGETOLINE3D Convert a 3D edge to a 3D straight line.

   LINE = edgeToLine3d(EDGE)
   Returns the 3D straight line containing the 3D edge EDGE.
   EDGE is represented as [X1 Y1 Z1  X2 Y2 Z2]
   LINE is represented as [X0 Y0 Z0  DX DY DZ]

   Example
       edge = [3 4 5  4 6 8];
       line = edgeToLine3d(edge)
       line = 
            3   4   5   1   2   3

   See also
     lines3d, edges3d, edgeToLine, lineToEdge3d

Package: matgeom