Hi!
On Mon, Feb 12, 2001 at 04:02:38PM -0500, Ricardo Guzman wrote:
How does ginac handle rational expressions internally? I see how polynomials in general are represented through the 'expairseq'
Thanks- So you use the 'lst' data structure to maintain this paired representation? Ricardo ----- Original Message ----- From: "Christian Bauer" <cbauer@student.physik.uni-mainz.de> To: <ginac-list@thep.physik.uni-mainz.de> Sent: Monday, February 12, 2001 4:17 PM Subject: Re: rational functions framework.
expairseq can store negative powers of expressions as well: 1/x = x^(-1)
But, how does it manipulate a quotient of two polynomials in the case of
gcd
calculations or when querying for numerator/denominator?
normal(), numer() and denom() internally split each (sub-)expression into a {numerator,denominator} pair. For example, normal() performs:
1/x+2 -> {1,x}+{2,1} -> {1+2x,x} -> (1+2x)/x (= (1+x^2)*x^(-1))
But this internal paired representation is not visible to the user.
Bye, Christian
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