denominator of really complicated expression

Ryan Krauss wrote:

> I use the SciPy Python module for all my numerical analysis and Python
> as my general programing language.  For this particular problem, I
> plan to use SciPy to do some numerical optimization.
> 
> Basically, Python is the language I am most comfortable with and I am
> trying to use Maxima only to do the symbolic part of this work.
> 
> I have done all that things I want to do for a farily simple example
> and I am just running into these problems with a more realistic
> problem.
> 
> If I was going to try and do everything in Maxima, the first thing I
> would need to know if how to do numerical root finding 
polynomial rootfinding is  called allroots.  That would work
for polynomials in one variable.
and
> optimization using things like Newton-Raphson and Nelder-Mead.
I don't know about Nelder-Mead, but there is a Mathematica
source code program on
http://math.fullerton.edu/mathews/n2003/NelderMeadMod.html
So it can't be more than a half-page of code for Maxima, too.
  and Newton's method surely has been programmed in various forms
in Maxima.

So you need not use SciPy. Though if it works for you, fine.

RJF
> 
> Ryan
> 
> On 11/23/05, Richard Fateman  wrote:
> 
>>It is quite reasonable to expect Python or some other
>>language processor to just break when given such a
>>large expression to parse.
>>
>>If what you want to do is evaluate this expression
>>for some particular values of the variables, I suggest
>>you just do it in maxima. You can even convert it to
>>lisp and compile to machine language.
>>
>>The chance that an expression so large suffers from
>>disasterous numerical instability is non-zero.  It may
>>be appropriate to rearrange using horners rule, too.
>>
>>What do you plan to use python for?
>>RJF
>>
>>
>>Ryan Krauss wrote:
>>
>>
>>>So, following Richard's advice, I am able to get my calculations to
>>>run without crashing and much faster than before.  I have one
>>>additional problem though.  In the end, I need to output these
>>>expressions to a file so that they can be read into a Python program.
>>>Running stringout(filename,expression) takes 5-15 minutes for each of
>>>my expressions (there are currently 4 of them and it takes almost an
>>
>>...
>>
> 
> 
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