Re: Extracting polynomial coefficients?
- To: mathgroup@smc.vnet.net
- Subject: [mg11483] Re: Extracting polynomial coefficients?
- From: weber@math.uni-bonn.de (Matthias Weber)
- Date: Fri, 13 Mar 1998 12:21:28 -0500
- Organization: RHRZ - University of Bonn (Germany)
- References: <6e87es$nlo@smc.vnet.net>
In article <6e87es$nlo@smc.vnet.net>, Thomas Bell <tombell@leland.Stanford.EDU> wrote: > I have a very long polynomial that's a function of four variables, a, b, > c, d. I would like Mathematica to (1) tell me what combinations of a, > b, c, and d are in my polynomial, and (2) tell me what the coefficients > are for each of the variable terms. > > For example, say I have constant terms r and q. My polynomial might > look something like > > 4 a^2 b^3 c + r q d^5 + a d^3 + q c^2 a^2 + r^2 a d^3 > > I would like to have Mathematica output something like: > > a^2 b^3 => 4 > d^5 => r q > a d^3 => 1 + r^2 > c^2 a^2 => q > > The polynomial is long enough that it would be very time-consuming to > search through and identify all the combinations of (a,b,c,d). > > Any help appreciated. Thanks. Have a look at the functions Coefficient CoefficientList Dimensions They are likely to do what you need. Matthias