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scipy.special.gdtr¶
- scipy.special.gdtr(a, b, x) = <ufunc 'gdtr'>¶
Gamma distribution cumulative density function.
Returns the integral from zero to x of the gamma probability density function,
F=∫x0abΓ(b)tb−1e−atdt,where Γ is the gamma function.
Parameters: a : array_like
The rate parameter of the gamma distribution, sometimes denoted β (float). It is also the reciprocal of the scale parameter θ.
b : array_like
The shape parameter of the gamma distribution, sometimes denoted α (float).
x : array_like
The quantile (upper limit of integration; float).
Returns: F : ndarray
The CDF of the gamma distribution with parameters a and b evaluated at x.
See also
- gdtrc
- 1 - CDF of the gamma distribution.
Notes
The evaluation is carried out using the relation to the incomplete gamma integral (regularized gamma function).
Wrapper for the Cephes [R363] routine gdtr.
References
[R363] (1, 2) Cephes Mathematical Functions Library, http://www.netlib.org/cephes/index.html