https://github.com/cran/pracma
Tip revision: 84a50252b184200bc6328ef733b7f94da0b64e4b authored by Hans W. Borchers on 29 May 2016, 21:34:12 UTC
version 1.9.3
version 1.9.3
Tip revision: 84a5025
conv.R
##
## c o n v . R Polynomial Convolution
##
conv <- function(x, y) {
if ( (!is.vector(x, mode="numeric") && !is.vector(x, mode="complex")) ||
(!is.vector(y, mode="numeric") && !is.vector(y, mode="complex")) )
stop("Arguments 'x' and 'y' must be real or complex vectors.")
lx <- length(x)
ly <- length(y)
n <- lx + ly - 1
z <- fft(fft(c(x, rep(0, n - lx))) * fft(c(y, rep(0, n - ly))),
inverse = TRUE) / n
if (is.numeric(x) && is.numeric(y))
z <- Re(z)
return(z)
}