Re: Re: Re: Re: Integration

*To*: mathgroup at smc.vnet.net*Subject*: [mg44476] Re: [mg44457] Re: [mg44444] Re: [mg44437] Re: Integration*From*: Andrzej Kozlowski <akoz at mimuw.edu.pl>*Date*: Wed, 12 Nov 2003 08:01:26 -0500 (EST)*References*: <bmg0li$e9k$1@smc.vnet.net> <bmj2os$prs$1@smc.vnet.net> <200311040823.DAA10480@smc.vnet.net> <200311051500.KAA26314@smc.vnet.net> <200311071016.FAA05417@smc.vnet.net> <boif1p$o9u$1@smc.vnet.net> <200311091101.GAA06766@smc.vnet.net> <200311100952.EAA17555@smc.vnet.net> <200311110055.TAA25159@smc.vnet.net>*Sender*: owner-wri-mathgroup at wolfram.com

No, not concrete grounds. However, I think any complex algorithm that has never been fully implemented is subject to doubt. The doubt need not concern just its mathematical correctness as is the case with proofs, but also practicability. If an algorithm is felt to be too complex to implement fully it seems likely that a "full implementation" will not perform reasonably in practice. In such cases the only value of a "full implementation" is the ability to claim that you have one. Actually, the situation with proofs is not so different. I know of more than one proof that has been published in a top class journal but when you privately asks experts in the field about it they turn out to be unsure of its correctness. These are extremely complex proofs that were accepted essentially because the referee could not find anything wrong with them and which very few people if anyone can inspect in every detail. In the case of algorithms implementation provides a more reliable test. Without one I think the algorithm has to be considered as doubtful. Andrzej Kozlowski Yokohama, Japan http://www.mimuw.edu.pl/~akoz/ On 11 Nov 2003, at 09:55, Murray Eisenberg wrote: > Do you have some basis for doubting the correctness of the Risch > algorithm? > > (Risch's work is described in a long paper in Transactions of Amer. > Math. Soc. and a shorter one in Bull. Amer. Math. Soc., both around > 1969-70. It's been a while since I've looked at those; I did not check > all the proofs myself.) > > Andrzej Kozlowski wrote: > >> Personally I am not even convinced that Risz's the algorithm correct. >> You obviously seem to know a better one so you would do everyone a >> favor if you implemented it for us, ort at least described it as a >> sequence of implementable steps. Now that's a challenge worth taking >> up. > > -- > Murray Eisenberg murray at math.umass.edu > Mathematics & Statistics Dept. > Lederle Graduate Research Tower phone 413 549-1020 (H) > University of Massachusetts 413 545-2859 (W) > 710 North Pleasant Street fax 413 545-1801 > Amherst, MA 01003-9305 > > >

**References**:**Re: Integration***From:*akhmel@hotmail.com (Alex)

**Re: Re: Integration***From:*Andrzej Kozlowski <akoz@mimuw.edu.pl>

**Re: Re: Re: Integration***From:*Murray Eisenberg <murray@math.umass.edu>

**Re: Integration***From:*akhmel@hotmail.com (Alex)

**Re: Re: Integration***From:*Andrzej Kozlowski <akoz@mimuw.edu.pl>

**Re: Re: Re: Integration***From:*Murray Eisenberg <murray@math.umass.edu>

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**Re: Re: Re: Integration**

**Re: Re: Integration**