https://github.com/cran/SoDA
Tip revision: dc000f2a5f006d137f66716b086025d618bf8306 authored by John M Chambers on 14 July 2008, 00:00:00 UTC
version 1.0-5
version 1.0-5
Tip revision: dc000f2
triDiag3.R
triDiag3 <- function(diagonal, upper, lower,
nrow = length(diagonal), ncol = nrow) {
value <- matrix(0, nrow = nrow, ncol = ncol)
r <-max(nrow, ncol)
if(r > 1) {
nu <- min(nrow, ncol-1)
nl <- min(nrow-1, ncol)
index <- outer((0:nu)*(nrow+1), 0:2, `+`)
value[index[1:min(nrow, ncol), 2]] <- diagonal
if(nu > 0)
value[index[-1, 1]] <- upper
if(nl > 0)
value[index[1:nl, 3]] <- lower
}
value
}