I'm not sure where your trouble is. You'll need to be more specific .... exactly what parameter values are causing you trouble?
I want to use Gamma distribution. It seems that there must be some constraints on Gamma distribution parameters, because:
1- the probability values in some cases become greater than one!
2-if beta is small and alpha is larges => beta^alpha=0 => probability=Inf
3-if alpah is larges => gamma(alpha)=Inf => probability=NaN
Dose anybody knows the constraints and what I can do in these situations?