From distr v1.8
0th

Percentile

The Gammad distribution with parameters shape $=\alpha$, by default = 1, and scale $=\sigma$, by default = 1, has density $$d(x)= \frac{1}{{\sigma}^{\alpha}\Gamma(\alpha)} {x}^{\alpha-1} e^{-x/\sigma}$$ for $x > 0$, $\alpha > 0$ and $\sigma > 0$. The mean and variance are $E(X) = \alpha\sigma$ and $Var(X) = \alpha\sigma^2$. C.f. rgamma

Keywords
distribution
##### Objects from the Class

Objects can be created by calls of the form Gammad(scale, shape). This object is a gamma distribution.

##### Extends

Class "ExpOrGammaOrChisq", directly. Class "AbscontDistribution", by class "ExpOrGammaOrChisq". Class "UnivariateDistribution", by class "AbscontDistribution". Class "Distribution", by class "UnivariateDistribution".

GammaParameter-class AbscontDistribution-class Reals-class rgamma

##### Aliases
G=Gammad(scale=1,shape=1) # G is a gamma distribution with scale=1 and shape=1.
scale(G)=2 # scale of this distribution is now 2.