https://github.com/cran/pracma
Tip revision: 9683335bbee02d0e5a569a07826d458ca55d5370 authored by HwB on 06 June 2012, 00:00:00 UTC
version 1.1.0
version 1.1.0
Tip revision: 9683335
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)
}