https://github.com/cran/pracma
Tip revision: a9b4d5f19cb88cd9d0d31fdde0d654737327d085 authored by HwB on 15 April 2012, 00:00:00 UTC
version 1.0.5
version 1.0.5
Tip revision: a9b4d5f
tri.R
##
## t r i . R Triangular matrices
##
tril <- function(M, k = 0) {
if (k == 0) {
M[upper.tri(M, diag = FALSE)] <- 0
} else {
M[col(M) >= row(M) + k + 1] <- 0
}
return(M)
}
triu <- function(M, k = 0) {
if (k == 0) {
M[lower.tri(M, diag = FALSE)] <- 0
} else {
M[col(M) <= row(M) + k - 1] <- 0
}
return(M)
}