another polynomial operation query



I am guessing at what you are trying to describe.

 

Perhaps it is this:

 

Given a polynomial p in variables x[1] .x[n] and a number k.  Expand p into
a sum of monomials. Find all monomials in p of the form

 

  C[i]*product(x[i]^e[i])   such that  the sum(e[i]) = exactly k.

 

Is that it?

 

Ratweight and ratwtlvl might do the job to find terms of total degree less
than or equal to k.

Or a multivariate taylor series expansion.

 

RJF

 

 

 

 

  _____  

From: maxima-bounces at math.utexas.edu [mailto:maxima-bounces at math.utexas.edu]
On Behalf Of Renatus
Sent: Tuesday, November 28, 2006 3:11 PM
To: maxima at math.utexas.edu
Subject: another polynomial operation query

 

I was a Reduce/PSL addict until I retired from professional life. To help
people I am still in contact with and who cannot afford the developer
version (and neither can I now !) I am trying to convert my former
Reduce/PSL programs to Maxima.

 

Recently there was a request for an operation on polynomials which begs for
the following generalisation:

 

Given a multivariate polynomial (perhaps in indeterminates on the form of an
array x of dimension n and non-commutative as well) return the list of its
homogeneous components. 

 

Simply return the homogeneous components of degree k if there is no more
efficient way to generate the required list than collecting the results from
k=0 up to the degree of the polynomial. (In fact I could not even find a
function returning the degree of a multivariate polynomial.)

 

Are such functions already hidden in some polynomial package ?  

 

Many thanks for any suggestion.

 

R J-M Grognard