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7.7.19.0. annRatSyz
Procedure from library dmodloc.lib (see dmodloc_lib).
- Usage:
- annRatSyz(f,g[,db,eng]); f, g polynomials, db,eng optional integers
- Assume:
- The basering is commutative and over a field of characteristic 0.
- Return:
- ring (a Weyl algebra) containing an ideal `LD', which is (part of)
the annihilator of the rational function g/f in the corresponding
Weyl algebra
- Remarks:
- This procedure uses the computation of certain syzygies.
One can obtain the full annihilator by computing the Weyl closure of
the ideal LD.
- Note:
- Activate the output ring with the
setring command.
In the output ring, the ideal `LD' (in Groebner basis) is (part of)
the annihilator of g/f.
If db>0 is given, operators of order up to db are considered,
otherwise, and by default, a minimal holonomic solution is computed.
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:
See also:
annPoly;
annRat.
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