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 GNU Scientific Library Reference Manual - Third Edition (v1.12) by M. Galassi, J. Davies, J. Theiler, B. Gough, G. Jungman, P. Alken, M. Booth, F. RossiPaperback (6"x9"), 592 pages, 60 figuresISBN 0954612078RRP £24.95 (\$39.95)

## 19.29 The Poisson Distribution

Function: unsigned int gsl_ran_poisson (const gsl_rng * r, double mu)
This function returns a random integer from the Poisson distribution with mean mu. The probability distribution for Poisson variates is,
p(k) = {\mu^k \over k!} \exp(-\mu)


for k >= 0.

Function: double gsl_ran_poisson_pdf (unsigned int k, double mu)
This function computes the probability p(k) of obtaining k from a Poisson distribution with mean mu, using the formula given above.

Function: double gsl_cdf_poisson_P (unsigned int k, double mu)
Function: double gsl_cdf_poisson_Q (unsigned int k, double mu)
These functions compute the cumulative distribution functions P(k), Q(k) for the Poisson distribution with parameter mu.
 ISBN 0954612078 GNU Scientific Library Reference Manual - Third Edition (v1.12) See the print edition