Esempio n. 1
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 /**
  * 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->lambda);
 }
Esempio n. 2
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 /**
  * Returns a random float between $lambda and $lambda plus $k
  * 
  * @param float $lambda The scale parameter. Default 1.0
  * @param float $k The shape parameter. Default 1.0
  * @return float The random variate.
  */
 public function getRvs($lambda = 1, $k = 1)
 {
     $e = $this->exp->getRvs(1);
     return $e == 0 ? 0 : $lambda * pow($e, 1 / $k);
 }