areapoly {spatialkernel}R Documentation

Signed Area of Polygon

Description

Calculate the area of a polygon and its boundary direction.

Usage

areapoly(poly)

Arguments

poly matrix containing the x,y-coordinates of the vertices of the polygon boundary.

Value

area positive numeric, the area of the polygon.
sign integer, 1 if the polygon orientation is anticlockwise, -1 otherwise.
poly copy of the passed argument poly.

Note

This function is provided here so that users do not need to load other packages, as it is not available in the base R packages.

References

Joseph O'Rourke, Computational Geometry in C (2nd Edition), Cambridge University Press, 2000 edition.


[Package spatialkernel version 0.4-8 Index]