https://github.com/cran/pracma
Tip revision: 3fdb68cc842f2ab3b59608f8e04d495763584f78 authored by Hans W. Borchers on 27 November 2015, 12:07:10 UTC
version 1.8.8
version 1.8.8
Tip revision: 3fdb68c
roots.R
###
### ROOTS.R Matlab ROOTS Function
###
roots <- function(p) {
if (is.null(p) || length(p) == 0) return(matrix(0, nrow=0, ncol=0))
if ( !is.vector(p, mode="numeric"))
stop("Argument p must be a vector of real numbers.")
if (length(p) == 1) return(matrix(0, nrow=0, ncol=0))
# Find non-zero entries in p
inz <- which(p != 0)
nnz <- length(inz)
if (nnz == 0) return(c())
# Strip leading and trailing zeros, but remember the trailing zeros
q <- p[inz[1]:inz[nnz]]
r <- rep(0, length(p) - inz[nnz])
A <- compan(q)
return(c(r, eig(A)))
}