Re: [Gretl-users] Factorial
El Martes, 10 de Octubre de 2006 17:03, Riccardo (Jack) Lucchetti escribió:
On Tue, October 10, 2006 16:43, Ignacio Díaz-Emparanza wrote:
> Is there a way to use a factorial of a number in a "genr" formula?
> I do not find it in the manual.
>
> I mean for example
> genr F = 4! (=4x3x2x1)
you can use the gamma() function, as in
genr a = 4
genr F = gamma(a+1)
Thank you for all the responses. This is valid for for me today.
(( May be we need an alias "factorial(x)" for that function? ))
If you need it for things like hypergeometric functions, which involve
ratios, we also have the lngamma() function, which gives numerically better
results.
(The problem was the multinomial function and it is solved with your
suggestion.)
--
Ignacio Díaz-Emparanza
Dpto. de Economía Aplicada III (Econometría y Estadística)
UPV-EHU