Efficent way to create an nxn upper triangular matrix of one's
Try x <- diag(n) x[upper.tri(x)] <- 1
On Wed, Feb 11, 2009 at 1:22 PM, Dale Steele <dale.w.steele at gmail.com> wrote:
The code below create an nxn upper triangular matrix of one's. I'm
stuck on finding a more efficient vectorized way - Thanks. --Dale
n <- 9
data <- matrix(data=NA, nrow=n, ncol=n)
data
for (i in 1:n) {
data[,i] <- c(rep(1,i), rep(0,n-i))
}
data
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