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paramBpoly(RingElement,File) -- compute the list of all possible Bernstein-Sato polynomials for a parametric polynomial

Synopsis

Description

This function computes the finite list of all possible Bernstein-Sato polynomials for a polynomial with parametric coefficients and creates latex code describing strata in the parameter space corresponding to the B.-S. polynomials --- each stratum is a constructible set. This is an implementation of the algorithmic approach in Anton Leykin. Constructibility of the Set of Polynomials with a Fixed Bernstein-Sato Polynomial: an Algorithmic Approach. Journal of Symbolic Computation, 32(6):663–675, 2001.
i1 : A =  (QQ [a,b,c]) [x, y, Dx, Dy, WeylAlgebra => {x=>Dx, y=>Dy}]

o1 = A

o1 : PolynomialRing, 2 differential variable(s)
i2 : paramBpoly(a*x^2 + b*x*y + c*y^2, stdio)
\begin{itemize}
\item $b(s)=(S+1)^2$ corresponds to
$V(0)$$\setminus$$V(b^2-4*a*c)$
\item $b(s)=(S+1/2)*(S+1)$ corresponds to
$V(b^2-4*a*c)$
\end{itemize}

             2       1
o2 = {(S + 1) , (S + -)(S + 1)}
                     2

o2 : List

Caveat

A finite field ZZ/p is used to speed up computations. Option "ground field" may be used to change the characteristic p. If p=0 the computation will be attempted over QQ.

See also

Ways to use this method: