Mathematica on linux help and Mathematica returns wrong integral result

*To*: mathgroup at smc.vnet.net*Subject*: [mg19431] Mathematica on linux help and Mathematica returns wrong integral result*From*: psalzman at landau.ucdavis.edu*Date*: Tue, 24 Aug 1999 01:29:28 -0400*Sender*: owner-wri-mathgroup at wolfram.com

dear all, i have Mathematica for students, version 3.1 running on suse linux 6.1 with enlightenment (no gnome or kde). very often when i want to click on something, the cursor (which is normally a pointer) becomes a hand and won't allow me to position it where i want. for instance, i'm looking at the "help browser" right now, and i looked at "factor" because i want to find out how to factor a pi/2 in front of an expression. it says "See also FactorTerms" as a blue hyperlink. under windows, when i click on that, the help browser would display the help for FactorTerms. here, when i go to click on it, the cursor becomes a hand and won't let me click on it. this is kind of annoying -- can someone tell me how to avoid this? at the very least, i want to be able to click on hyperlink help topics that appear in the help browser. =========================================================================== wrong result i've definitely confirmed that Mathematica definitely gives a wrong result for an integral. i've have an integral which contains a product of 3 bessel function of half order. i expressed this integral in 3 ways -- converting no bessel functions as sin x/x, converting 1 bessel function as sin[x]/x, converting 2 besselfunctions as sin x/x and converting all 3 as sin x/ x. the expressions are all equal, and the result that Mathematica gives is *almost* correct. the correct result was given by converting all bessel functions as sin x/x, and i verified this by doing a very difficult contour integration (see what Mathematica made me do?) :) i was very careful and thorough, and my answer agrees completely with the Mathematica result of converting all bessel functions into sin x / x. the other 3 answers that Mathematica gave are numerically very close -- they differ by numbers on the order of 10^-21 and include very, very small log terms. what seems to be happening is Mathematica isn't recognizing terms which ought to be pure zero. instead, they're simply (very) small. this may be a machine precision thing, but i'm sufficiently dumb about Mathematica's algorithms that i simply don't know. in any event, how do i contact wolfram about this to give details? should i mail them my work? do they really want to see hardcore math relating to my research? like i said, they're very, very close, numerically. does anyone care about this? thanks! pete