/** * Returns the moments of the distribution * * @param string $moments Which moments to compute. m for mean, v for variance, s for skew, k for kurtosis. Default 'mv' * @return type array A dictionary containing the first four moments of the distribution */ public function stats($moments = 'mv') { return $this->calculator->getStats($moments, $this->k, $this->theta); }
/** * Returns a random float between $alpha and $alpha plus $beta * * @param float $alpha The minimum parameter. Default 0.0 * @param float $beta The maximum parameter. Default 1.0 * @return float The random variate. */ public function getRvs($alpha = 1, $beta = 1) { $x = $this->gamma->getRvs($alpha, 1); $y = $this->gamma->getRvs($beta, 1); return $x / ($x + $y); }