Date: Sep 14, 2013 1:53 PM
Author: clicliclic@freenet.de
Subject: Re: The integration test suites for Sage.

peter.luschny@gmail.com schrieb:

>

> I now have benchmarked SymPy 0.7.3, which was released

> on July 13, 2013. See the release notes [1].

> An implementation for SymPy can be found at github [2].

> The results are listed at [3].

>

> [1] https://github.com/sympy/sympy/wiki/Release-Notes-for-0.7.3

> [2] https://github.com/PeterLuschny/CharlwoodTest

> [3] http://luschny.de/math/quad/IntegralTestsSympy.html

Your tests of the SymPy integrator reveal a glaring weakness in the

algebraic arena (most of Charlwood; Timofeev 124, 154-159, 165), and a

lesser one in the rational trigonometric arena (Charlwood 37; Timofeev

108, 114-117, 131, 162). So SymPy's Risch implementation doesn't really

cover trigonometric functions yet. Also Sympy's trigonometric

simplification fails to confirm many valid antiderivatives.

>

> > PS: How about contributing a chapter of the Timofeev suite yourself?

>

> Hm, my Russian is a little bit rosty, Genosse Martin!

No knowledge of Russian is needed to copy mathematical expressions from

a 20th century Russian book, and your appeal to comradeship doesn't make

this fact disappear. Some knack for mathematical puzzle solving is

needed, however, to undo any misprints in Timofeev's integrands with the

help of his evaluations. The "examples" for Chapter 5 start near the

bottom of page 202, for integral #4 you turn pages until you reach the

next example section on page 208. Subsequent sections start on pages

211, 213, 219, 223, and so on.

No more flimsy excuses!

Martin.