area3D

A function for area of a 3D planar polygon.polygon which does

A function which gives the area of a 3D planar polygon which does not lie in the x-y plane.

AREA3D(X,Y,Z) calculates the area of a polygon in space formed by vertices with coordinate vectors X,Y and Z. If the coordinates of vertex v_i are x_i, i and z_i twice the area of a polygon is given by:

2 A(P) = abs(N . (sum_{i=0}^{n-1} (v_i x v_{i+1})))

where N is a unit vector normal to the plane.

The '.' represents the dot product operator, the 'x' represents the cross product operator, and abs() is the absolute value function.

Tested under MATLAB 5.3