Squares function

Areas of polygons

Calculates areas of polygons

Squares(ppts, relative=FALSE)

Arguments

• ppts: Output from Hulls() or Ellipses(), or just a list of polygons
• relative: Calculate relative squares?

Details

"List of polygons" must be the list which contains any number of two-column numerical matrices of data frames, each represents the vertices of one polygon.

Might be useful to understand the variability of groups.

Returns

Numerical (possibly named) vector of polygon areas, one element per polygon.

Author(s)

Alexey Shipunov

See Also

Hulls, Ellipses

Examples

iris.pca <- prcomp(iris[, -5])
iris.p <- iris.pca$x[, 1:2]

iris.h <- Hulls(iris.p[, 1:2], as.numeric(iris[, 5]), plot=FALSE)
Squares(iris.h, relative=TRUE)

iris.e <- Ellipses(iris.p, iris$Species, plot=FALSE, centers=TRUE)
Squares(iris.e)