LogNormal probability distribution function.
LogNormal(g,mu,sigma2)
Generates a random variate following the LogNormal probability distribution function, with mean mu and variance sigma2.
The pseudo-code algorithm used for this distribution is:
1. Generate Y as N(mu,sigma2).
2. Return x = e^Y
(u,g) := LogNormal(g,0,1);
function LogNormal extends Var; end LogNormal;