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7.7.3.0. annfsLOT
Procedure from library dmod.lib (see dmod_lib).

Usage:
annfsLOT(F [,eng]); F a poly, eng an optional int

Return:
ring

Purpose:
compute the D-module structure of basering[1/f]*f^s, according to
the Levandovskyy's modification of the algorithm by Oaku and Takayama

Note:
activate the output ring with the setring command. In this ring,
- the ideal LD (which is a Groebner basis) is the needed D-module structure,
which is obtained by substituting the minimal integer root of a Bernstein
polynomial into the s-parametric ideal;
- the list BS contains the roots with multiplicities of BS polynomial of f.
If eng <>0, std is used for Groebner basis computations,
otherwise and by default slimgb is used.
If printlevel=1, progress debug messages will be printed,
if printlevel>=2, all the debug messages will be printed.

Example:
 
LIB "dmod.lib";
ring r = 0,(x,y,z),Dp;
poly F = z*x^2+y^3;
printlevel = 0;
def A  = annfsLOT(F);
setring A;
LD;
==> LD[1]=y*Dy+3*z*Dz+3
==> LD[2]=x*Dx-2*z*Dz
==> LD[3]=x^2*Dy-3*y^2*Dz
==> LD[4]=3*y^2*Dx-2*x*z*Dy
==> LD[5]=y^3*Dz+x^2*z*Dz+x^2
==> LD[6]=2*x*z*Dy^2+9*y*z*Dx*Dz+3*y*Dx
==> LD[7]=9*y*z*Dx^2*Dz+4*z^2*Dy^2*Dz+3*y*Dx^2+2*z*Dy^2
==> LD[8]=4*z^2*Dy^3*Dz-27*z^2*Dx^2*Dz^2+2*z*Dy^3-54*z*Dx^2*Dz-6*Dx^2
BS;
==> [1]:
==>    _[1]=-7/6
==>    _[2]=-5/6
==>    _[3]=-4/3
==>    _[4]=-1
==>    _[5]=-5/3
==> [2]:
==>    1,1,1,1,1


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