https://github.com/cran/nacopula
Tip revision: 161411bb86f97e5a8bd89091cd61d03a33c2761a authored by Martin Maechler on 06 February 2012, 00:00:00 UTC
version 0.8-0
version 0.8-0
Tip revision: 161411b
rlog.Rd
\name{rlog}
\alias{rlog}
\alias{rlogR}
\title{Sampling Logarithmic Distributions}
\description{
Generating random variates from a Log(p) distribution with probability
mass function
\deqn{p_k=\frac{p^k}{-\log(1-p)k},\ k\in\mathbf{N},
}{p_k = p^k/(-log(1-p)k), k in IN,}
where \eqn{p\in(0,1)}{p in (0,1)}. The implemented algorithm is the
one named \dQuote{LK} in Kemp (1981).
}
\usage{
rlog(n, p, Ip = 1 - p)
}
\arguments{
\item{n}{sample size, that is, length of the resulting vector of random
variates.}
\item{p}{parameter in \eqn{(0,1)}.}
\item{Ip}{\eqn{= 1 - p}, possibly more accurate, e.g, when
\eqn{p\approx 1}{p ~= 1}.}
}
\value{
A vector of positive \code{\link{integer}}s of length \code{n} containing the
generated random variates.
}
\details{
For documentation and didactical purposes, \code{rlogR} is a pure-\R
implementation of \code{rlog}. However, \code{rlogR} is not as fast as
\code{rlog} (the latter being implemented in C).
}
\author{Marius Hofert, Martin Maechler}
\references{
Kemp, A. W. (1981),
Efficient Generation of Logarithmically Distributed Pseudo-Random Variables,
\emph{Journal of the Royal Statistical Society: Series C (Applied
Statistics)} \bold{30}, 3, 249--253.
}
\examples{
## Sample n random variates from a Log(p) distribution and plot a
## histogram
n <- 1000
p <- .5
X <- rlog(n, p)
hist(X, prob = TRUE)
}
\keyword{distribution}