Problems with linsolve: quotient by polynomial of higher degree
Subject: Problems with linsolve: quotient by polynomial of higher degree
From: Richard Fateman
Date: Sat, 26 May 2012 07:27:13 -0700
On 5/26/2012 2:51 AM, Stefano Ferri wrote:
> me think that there is something related to the search for solutions
> for polynomials of degree > 5.
Not if the system is linear.
> Therefore my question is:
>
> Q - Is it possible to use linsolve as a general linear equations
> systems solvers,
If the system is indeed linear, it should work if the demands of memory
and time do not prevent it from finishing.
> or is it suitable only for solving the simplest cases?
depends on the growth in the size of the symbolic coefficients.
> Or is this a bug (in pquotient & c)?
pquotient is apparently free of bugs. It appears that some subtle bug in
the use of GCD is the cause. If Maxima
computes G=polynomialGCD(A,B), then the degree of G must be less than
the degrees of A or B.
But it isn't.
It may be that there is some conflict when terms with sqrt are
simplified and some processing decreases
the degree of A after the GCD.
Finding this bug would be nice, if indeed the system is linear etc.
In some cases a work-around is to use a different GCD algorithm, e.g.
setting gcd:red
RJF
>
> I'v