pGamma

pGamma(k, x, tail=False)

Cumulative distribution function of a Gamma distribution on [0,+\infty[.

Parameters:
kfloat

Shape parameter k > 0 with k = (\mu - \gamma)^2 / \sigma^2.

xfloat

Location.

tailbool, optional

Tail flag. Default value is False. If True, the complementary CDF is computed.

Returns:
pfloat

The CDF or the complementary CDF at x.

Notes

The probability density function is defined as:

f_X(x) = \frac{1}{\Gamma(k)} \left(x )\right)^{k - 1} \exp\left(- x)\right), \quad x \in [0; +\infty[

with k, \lambda > 0.

Examples

>>> import openturns as ot
>>> cdf = ot.DistFunc.pGamma(2.5, 0.9)