At Mon, 01 Oct 2007 21:27:32 +0200, Paul Zimmermann wrote: > we are about the implement a dilogarithm function in MPFR. Looking at the > different definitions, it seems the GSL definition is not the "standard" > one in the Abramowitz&Stegun sense, but more what is commonly designed as > Li2(x) [as the GSL manual admits it]. > > This is quite annoying, since if we introduce a function mpfr_dilog in > MPFR, it will be either inconsistent with A&S, or inconsistent with GSL, > and in both cases will probably confuse the users. > > One solution would be for us to only export a function mpfr_li2, which would > correspond to the "common" definition of Li2(x), and to the gsl_sf_dilog > function. > > Would that be ok for you? Can you explain why you choosed that mathematical > definition for gsl_sf_dilog, or that name instead of gsl_sf_li2?
Hello, Thanks for your email. If you want an unambiguous name then using mpfr_li2 would probably be the best choice. I believe the reason that GSL uses the name gsl_sf_dilog is that the dilogarithm is most commonly (correctly?) defined as Li2, and A&S is in the minority calling the Spence integral a dilogarithm. I've cc'ed this email to Gerard Jungman the original author of the GSL dilogarithm function for any further comments. -- Brian Gough GNU Scientific Library - http://www.gnu.org/software/gsl/ _______________________________________________ Help-gsl mailing list [email protected] http://lists.gnu.org/mailman/listinfo/help-gsl
