How can I set the coefficient domain of polynomials? Say, I want my coefficients to be in Z mod 17, i.e. Galois Field 17, what do I do? Also, as a more general question, I'd like to know if GiNac poses any overhead on the polynomial classes provided by CLN. In other words, it is less efficient to write polynomials routines in Normal.cpp (the polynomial module in GiNac) than directly work with the CLN classes? Thanks in advance for your answers! Wolfgang - To UNSUBSCRIBE, email to ginac-list@ginac.de with a subject of "unsubscribe".
HI! On Wed, Jul 04, 2001 at 10:19:12AM -0400, Wolfgang Abele wrote:
How can I set the coefficient domain of polynomials?
You can't.
Say, I want my coefficients to be in Z mod 17, i.e. Galois Field 17, what do I do?
You would have to manually adjust the coefficients after each operation. There's an smod() function in GiNaC for this, but this is a symmetric modulus.
In other words, it is less efficient to write polynomials routines in Normal.cpp (the polynomial module in GiNac) than directly work with the CLN classes?
Yes. GiNaC doesn't use CLN's polynomial type because we needed to work with a more general class of expressions. Bye, Christian -- / Coding on PowerPC and proud of it \/ http://www.uni-mainz.de/~bauec002/ - To UNSUBSCRIBE, email to ginac-list@ginac.de with a subject of "unsubscribe".
Hi Christian,
Yes. GiNaC doesn't use CLN's polynomial type because we needed to work with a more general class of expressions. Let's see if I understand the situation:
To implement polynomial factorization algorithms I could start coding for the CLN immediately because CLN lets me define polynomials in Z mod p? Could we include such a code in GiNac somehow? (Coefficients in Z mod p and modular arithmetic are a prerequisite for factorization algorithms.) By contrast, GiNaC's type offers multivariate polynomials and a gcd, but is less efficient, does not support coefficients Z mod p, and is altogether separated from CLN's number package? And if it's not asking too much: Could you give me a short code example on how to set a modular coefficient ring for polynomial computations in CLN? Thank you very much! Servus Wolfgang - To UNSUBSCRIBE, email to ginac-list@ginac.de with a subject of "unsubscribe".
participants (2)
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Christian Bauer
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Wolfgang Abele