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

Version History

Introduced before R2006a