udpois function

UNU.RAN object for Poisson distribution

UNU.RAN object for Poisson distribution

Create UNU.RAN object for a Poisson distribution with parameter lambda.

[Distribution] -- Poisson.

udpois(lambda, lb = 0, ub = Inf)

Arguments

  • lambda: (non-negative) mean.
  • lb: lower bound of (truncated) distribution.
  • ub: upper bound of (truncated) distribution.

Details

The Poisson distribution has density

p(x)=λxeλx!p(x)=lambdaxexp(lambda)/x! p(x) = \frac{\lambda^x e^{-\lambda}}{x!}p(x) = lambda^x exp(-lambda)/x!

for x=0,1,2,x = 0, 1, 2, \ldots.

The domain of the distribution can be truncated to the interval (lb,ub).

Returns

An object of class "unuran.discr".

See Also

unuran.discr.

References

N.L. Johnson, S. Kotz, and A.W. Kemp (1992): Univariate Discrete Distributions. 2nd edition, John Wiley & Sons, Inc., New York. Chap. 4, p. 151.

Author(s)

Josef Leydold and Wolfgang H"ormann unuran@statmath.wu.ac.at .

Examples

## Create distribution object for Poisson distribution dist <- udpois(lambda=2.3) ## Generate generator object; use method DARI gen <- darid.new(dist) ## Draw a sample of size 100 x <- ur(gen,100)
  • Maintainer: Josef Leydold
  • License: GPL (>= 2)
  • Last published: 2025-04-07