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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)

## 19.7 The Exponential Power Distribution

Function: double gsl_ran_exppow (const gsl_rng * r, double a, double b)
This function returns a random variate from the exponential power distribution with scale parameter a and exponent b. The distribution is,
p(x) dx = {1 \over 2 a \Gamma(1+1/b)} \exp(-|x/a|^b) dx


for x >= 0. For b = 1 this reduces to the Laplace distribution. For b = 2 it has the same form as a gaussian distribution, but with a = \sqrt{2} \sigma.

Function: double gsl_ran_exppow_pdf (double x, double a, double b)
This function computes the probability density p(x) at x for an exponential power distribution with scale parameter a and exponent b, using the formula given above.

Function: double gsl_cdf_exppow_P (double x, double a, double b)
Function: double gsl_cdf_exppow_Q (double x, double a, double b)
These functions compute the cumulative distribution functions P(x), Q(x) for the exponential power distribution with parameters a and b.
 ISBN 0954612078 GNU Scientific Library Reference Manual - Third Edition (v1.12) See the print edition