https://github.com/cran/fields
Tip revision: c71fb7f6ffa323303affebf0e35a0070faa9c24d authored by Doug Nychka on 10 May 2004, 00:00:00 UTC
version 1.7.2
version 1.7.2
Tip revision: c71fb7f
sim.rf.default.r
"sim.rf.default" <-
function (obj)
{
n <- obj$n
m <- obj$m
M <- obj$M
N <- obj$N
if (any(Re(obj$wght) < 0)) {
stop("FFT of covariance has negative\nvalues")
}
z <- fft(matrix(rnorm(N * M), ncol = N, nrow = M))
Re(fft(sqrt(obj$wght) * z, inverse = TRUE))[1:m, 1:n]/sqrt(M *
N)
}