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"nsimplex"<-
function(p, n)
{
# DATE WRITTEN: 24 Dec 1997 LAST REVISED: 24 Dec 1997
# AUTHOR: Scott D. Chasalow (Scott.Chasalow@users.pv.wau.nl)
#
# DESCRIPTION:
# Computes the number of points on a {p, n}-simplex lattice; that is, the
# number of p-part compositions of n. This gives the number of points in
# the support space of a Multinomial(n, q) distribution, where
# p == length(q).
#
# Arguments p and n are replicated as necessary to have the length of the
# longer of them.
#
# REQUIRED ARGUMENTS:
# p vector of (usually non-negative) integers
# n vector of (usually non-negative) integers
#
mlen <- max(length(p), length(n))
p <- rep(p, length = mlen)
n <- rep(n, length = mlen)
out <- nCm(n + p - 1, n)
out[p < 0] <- 0
out
}
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