centroid.scaled.distances: Calculate the matrix of distances between shape coordinates,...

In aphanotus/borealis: Tools for reproducible geometric morphometric analysis

Calculate the matrix of distances between shape coordinates, scaled by centroid size

Description

Calculate the matrix of distances between shape coordinates, scaled by centroid size

Usage

centroid.scaled.distances(m, scale = TRUE, symmetrical = FALSE)

Arguments

m	A matrix containing XY shape coordinates for p landmarks
scale	A logical argument for whether to scale the distances by centroid size
symmetrical	A logical argument for whether to keep the output matrix symmetrical. If symmetrical = FALSE (the default) then the upper triangle and diagonal cells will be NA.

Value

Returns a matrix, with dimensions p x p.

Source

Dave Angelini [e-mail] [aut, cre]

Examples

x <- matrix(c(9,49, 24,54, 51,28, 81,54, 81,23, 86,32), ncol = 2, byrow = TRUE)

centroid.scaled.distances(x)
centroid.scaled.distances(x, symmetrical = TRUE)
centroid.scaled.distances(x, symmetrical = TRUE, scale = FALSE)

# cross validation
df <- data.frame(matrix(nrow = dim(x)[1], ncol = dim(x)[1]))
for (i in (1:dim(x)[1])) {
  df[i,] <- unlist(apply(x, 1, distance, XY=x[i,]))
}
df

aphanotus/borealis documentation built on Nov. 4, 2022, 8:44 p.m.