R/corw.R

In stnava/itkImageR: Examples using Rcpp to interface R and ITK

corw <- function(mat, weights) {
  if (missing(mat) | missing(weights)) {
    print(args(corw))
    return(1)
  }
  cormat <- matrix(rep(NA, ncol(mat) * ncol(mat)), ncol = ncol(mat))
  for (x in 1:ncol(mat)) {
    for (y in 1:ncol(mat)) {
      cormat[x, y] <- sqrt(summary(lm(mat[, x] ~ mat[, y]), weights = weights/sum(weights))$r.squared)
      # cormat[x,y]<-corr( cbind(mat[,x], mat[,y]), w = weights/sum(weights) )
    }
  }
  return(cormat)
}