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- Function:
*void***gsl_ran_multinomial***(const gsl_rng **`r`, size_t`K`, unsigned int`N`, const double`p`[], unsigned int`n`[]) -
This function computes a random sample

`n`[] from the multinomial distribution formed by`N`trials from an underlying distribution`p`[`K`]. The distribution function for`n`[] is,P(n_1, n_2, ..., n_K) = (N!/(n_1! n_2! ... n_K!)) p_1^n_1 p_2^n_2 ... p_K^n_K

where

*(n_1, n_2, ..., n_K)*are nonnegative integers with*sum_{k=1}^K n_k = N*, and*(p_1, p_2, ..., p_K)*is a probability distribution with*\sum p_i = 1*. If the array`p`[`K`] is not normalized then its entries will be treated as weights and normalized appropriately. The arrays`n`[] and`p`[] must both be of length`K`.Random variates are generated using the conditional binomial method (see C.S. Davis, The computer generation of multinomial random variates, Comp. Stat. Data Anal. 16 (1993) 205–217 for details).

- Function:
*double***gsl_ran_multinomial_pdf***(size_t*`K`, const double`p`[], const unsigned int`n`[]) This function computes the probability

*P(n_1, n_2, ..., n_K)*of sampling`n`[`K`] from a multinomial distribution with parameters`p`[`K`], using the formula given above.

- Function:
*double***gsl_ran_multinomial_lnpdf***(size_t*`K`, const double`p`[], const unsigned int`n`[]) This function returns the logarithm of the probability for the multinomial distribution

*P(n_1, n_2, ..., n_K)*with parameters`p`[`K`].