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Re: graphing traces of complicated evaluations (improved)

  • To: mathgroup at smc.vnet.net
  • Subject: [mg79298] Re: graphing traces of complicated evaluations (improved)
  • From: dimitris <dimmechan at yahoo.com>
  • Date: Tue, 24 Jul 2007 05:59:27 -0400 (EDT)
  • References: <f81m7n$lm0$1@smc.vnet.net>

On 23     , 10:43, chuck009 <dmili... at comcast.com> wrote:
> Hello Dimitris,
>
> Do you know how to "manually" calculate an analytic solution to this integral?  Suppose I can look up convolution method and Risch algorithm.  Also, I suspect there are "internal" debugging tools at Wolfram that would allow a "sharp" programmer there to track down where the error is occurring.  I could if it were my code :)
>
>
>
>
>
> > the integral is evaluated with the convolution
> > method.
>
> > (BTW, the integral is not a trivial one for the Risch
> > algorithm.
>
> > Professor R. Fateman some time ago wrote to me...
>
> > "While it may not seem hard to you, it turns out that
> > there are three
> > components to the Risch integration algorithm:
> > exponential, log and
> > algebraic.
> > this integrand, if it is done using the Risch
> > algorithm, requires that
> > all of them work, together.
>
> > Since there is not, so far as I know, a complete
> > implementation of the
> > algebraic case in Mathematica, there may be problems
> > with
> > the hacks taken to bypass this lack of
> > implementation.
> > So I don't find the issue to be surprising."
> > )
>
> > Somewhere during the process something went wrong.
>
> > I don't see how you could detect where it happens
> > this failure
> > (bear in mind that it might be one place that the
> > code fails; or
> > even more than one place!)
> > Only someone with a good knowledge of symbolic
> > algebra could
> > do such a task...
>
> > Dimitris-                               -
>
> -                               -

No!
Having tried a lot of things, I gae up!
I hope someone other will find a correct closed form solution
for this integral.

Dimitris



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