wblstat

Weibull mean and variance

Syntax

`[M,V] = wblstat(A,B)`

Description

`[M,V] = wblstat(A,B)` returns the mean of and variance for the Weibull distribution with scale parameter, `A` and shape parameter, `B`. Vector or matrix inputs for `A` and `B` must have the same size, which is also the size of `M` and `V`. A scalar input for `A` or `B` is expanded to a constant matrix with the same dimensions as the other input.

The mean of the Weibull distribution with parameters a and b is

`$a\left[\Gamma \left(1+{b}^{-1}\right)\right]$`

and the variance is

`${a}^{2}\left[\Gamma \left(1+2{b}^{-1}\right)-\Gamma {\left(1+{b}^{-1}\right)}^{2}\right]$`

Examples

```[m,v] = wblstat(1:4,1:4) m = 1.0000 1.7725 2.6789 3.6256 v = 1.0000 0.8584 0.9480 1.0346 wblstat(0.5,0.7) ans = 0.6329```