Hi, You could make use of the relation (say G for Gamma):
G(x)=G(x+1)/x -1<x<0 [1] and recursively compute Gamma for any negative, non-integer, x. When first dealing with Gamma function I found this [2] document particulary useful. You can download a ps version from there. Regards, Iñigo [1] Abramowitz and Stegun. Handbook of Mathematical Functions. Eq. 6.1.15 http://www.math.sfu.ca/~cbm/aands/page_256.htm [2] http://numbers.computation.free.fr/Constants/Miscellaneous/gammaFunction.html El Thursday, 10 de August de 2006 04:00, Marc Normandin escribió: > Hello, > > I require the computation of ln of the gamma function for all negative > non-integer values. The reflection formula can be used for half of the > negative non-integers along with the log since for half the values will be > positive. However, I would like to obtain a value for the other half. I'm > using the ln of gamma as an intermediate step after which I raise the > result with an exponential, so that ultimately I am not after the actual > value of ln gamma itself. I am open to any methods that work. > > At the current time the only way that I've found to compute the ln of gamma > for negative non-integer values is to treat the argument as a complex > number z = -x + 0i and then use Ln(z) = ln(|z|) + iPI, for the term > involving the sin from the relfection formula. > > I'd appreciate help and suggestions. > > Thanks, > Marc. > _______________________________________________ > Help-gsl mailing list > [email protected] > http://lists.gnu.org/mailman/listinfo/help-gsl _______________________________________________ Help-gsl mailing list [email protected] http://lists.gnu.org/mailman/listinfo/help-gsl
