Dieter Kaiser wrote:
> I have further added some code to simpgamma to expand expressions like
> gamma(n*z) and gamma(z+n) with n an integer. The expansion depends on a flag
> $gammaexpand. Especially specint gives with this code not in all cases but often
> a much more simple result.
>
> Here are examples:
>
> (%i25) gamma(2*z);
> (%o25) 2^(2*z-1)*gamma(z)*gamma(z+1/2)/sqrt(%pi)
This seems less useful, usually, but is certainly beneficial in the
example you give later.
>
> (%i26) gamma(z+1);
> (%o26) z*gamma(z)
>
> (%i27) gamma(z-1);
> (%o27) -gamma(z)/(1-z)
The first is quite useful. Not sure about z-1.
>
> (%i28) gamma(z+1)/gamma(z);
> (%o28) z
This example is handled by minfactorial. Well, you do have to call
makefact first. I think minfactorial should recognize gamma as well as
factorial.
Would it be better to have a function to apply this simplifications,
like we have with minfactorial and factcomb. There doesn't seem to be a
way to convert (z+1)! to z!*(z+1).
Just some random questions. I don't really have a problem with you've done.
Ray