TRIANGLEAREA3D Area of a 3D triangle.

   AREA = triangleArea3d(P1, P2, P3)
   Computes area of the 3D triangle whose vertices are given by P1, P2 and
   P3. Each vertex is either a 1-by-3 row vector, or an array with 3
   columns, each column representing coordinate of a vertex.
   The result AREA has as many rows as the number of rows of the largest
   input array.
   Compared to polygonArea3d, this function is assumed to be faster, as it
   does not requires iteration over vertices. Moreover, it can be used to
   computes the area of several triangles simultaneously.

   AREA = triangleArea3d(PTS)
   Concatenates vertex coordinates in a 3-by-3 array. Each row of the
   array contains coordinates of one vertex.


   Example
   triangleArea3d([10 10 10], [30 10 10], [10 40 10])
   ans = 
       300

   See also
   polygons3d, polygonArea3d

 ------
 Author: David Legland
 e-mail: david.legland@grignon.inra.fr
 Created: 2011-08-23,    using Matlab 7.9.0.529 (R2009b)
 Copyright 2011 INRA - Cepia Software Platform.

Package: matgeom