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7.7.1.0. bfctAnn
Procedure from library bfun.lib (see bfun_lib).

Usage:
bfctAnn(f [,r]); f a poly, r an optional int

Return:
list of ideal and intvec

Purpose:
computes the roots of the Bernstein-Sato polynomial b(s) for the
hypersurface defined by f.

Assume:
The basering is commutative and of characteristic 0.

Background:
In this proc, ann(f^s) is computed and then a system of linear
equations is solved by linear reductions.

Note:
In the output list, the ideal contains all the roots and the intvec
their multiplicities.
If r<>0, std is used for GB computations,
otherwise, and by default, slimgb is used.

Display:
If printlevel=1, progress debug messages will be printed,
if printlevel>=2, all the debug messages will be printed.

Example:
 
LIB "bfun.lib";
ring r = 0,(x,y),dp;
poly f = x^2+y^3+x*y^2;
bfctAnn(f);
==> [1]:
==>    _[1]=-5/6
==>    _[2]=-7/6
==>    _[3]=-1
==> [2]:
==>    1,1,1


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