Polygon Area
The (signed) area of a planar non-self-intersecting polygon with vertices
, ...,
is
where
denotes a determinant.
This can be written
where the signs can be found from the diagram above.
Note that the area of a convex polygon is defined to be positive if the points are arranged in a counterclockwise order, and negative if they are in clockwise order (Beyer 1987).
polygon area




