which packages do I need to use 'integral' function?

which packages do I need to use 'integral' function? I type it on command line in 2011b and get an "Undefined function" error

>> fun = @(x) exp(-x.^2).*log(x).^2;
>> q = integral(fun,0,Inf)

Undefined function 'integral' for input arguments of type 'function_handle'.

[Xin]

it worked. thanks a lot for the answers and suggestions.

Answer 1

[Andrei Bobrov]

use function quadgk

eg

>> fun = @(x) exp(-x.^2).*log(x).^2;
>> quadgk(fun,0,inf)
ans =
       1.9475

Answer 2

[Ilham Hardy]

It is Matlab standard function, only available in R2012b.

[Andrei Bobrov]

2012a

Answer 3

[Andreas Goser]

This was introduced in R2012a:

"The new functions, integral, integral2, and integral3 perform numerical integration with additional support for nonrectangular and unbounded regions of integration. They are the recommended functions for performing quadrature."