Re: Simple integral problem

*To*: mathgroup at smc.vnet.net*Subject*: [mg32697] Re: Simple integral problem*From*: kkumer at phy.hr (Kresimir Kumericki)*Date*: Thu, 7 Feb 2002 05:09:20 -0500 (EST)*Organization*: Theor.Phys.Dept, Univ. of Zagreb, Croatia*References*: <a3qr0b$28q$1@smc.vnet.net>*Sender*: owner-wri-mathgroup at wolfram.com

Rolf Mertig <rolf at mertig.com> wrote: > wasn't it Lenin who said "Trust is good, control is better"? Ah, those philosophers of old times! They knew. > Long years ago I made a large table of integrals similar to yours. And for a similar purpose, I presume. I need these for Feynman diagrams calculation in particle physics. BTW, I'm already using your FeynCalc package for checking my calculations but mostly for the Dirac algebra. I haven't used this Integrate2[] as yet, since I thought that the main advantage with respect to Integrate[] would be speed and this is not an issue in my small calculations. Thanks for drawing my attention to it, and thanks to other guys who responded for their thoughts. > you don´t have to rely on functions like Integrate which are tremendously > difficult to have bug-free. But the the pattern matcher and the programming > language are rather bug-free ... I certainly agree with you here that pattern matching algorithms are easier to do bug-free. In fact, since computer memory and storage space is so cheap these days, and if integration algorithms are so difficult as you say, probably the people in Wolfram Research should also implement integration through a large lookup table. On the other hand, I really cannot believe that this bug I discovered is so hard to avoid. If it is, then this should be stated on the very first page of the Mathematica book. I am disappointed that I cannot trust Mathematica with such a simple integral. -- Kresimir Kumericki kkumer at phy.hr http://www.phy.hr/~kkumer/ "Fizika svemira" - http://eskola.hfd.hr/fizika_svemira/svemir.html