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gamma(), gamma_r()

The gamma() and gamma_r() functions both compute the logarithm of the gamma function. They are synonyms for lgamma and lgamma_r.

double gamma(double x);
double gamma_r(double x, int *);

Note

Despite their names, these functions compute the logarithm of the gamma function, not the gamma function itself. To compute the gamma function itself, use tgamma().

Note

These functions are deprecated.