R/gdif.r

In Morpho: Calculations and Visualisations Related to Geometric Morphometrics

gdif <- function (a3) 
{
#### this is a modified copy of the function "dif" from the shapes package ####
#### Copyright by Ian Dryden
    cc <- cSize(addo(a3)/dim(a3)[3])
    x <- sweep(a3, c(1, 2), arrMean3(a3))
    z <- sqrt(sum((as.vector(x)/cc)^2/dim(a3)[3])^2)
	
    return(z)
}