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HilbertSeriesMultiDeg

the Hilbert-Poincare series wrt a multigrading

Syntax
HilbertSeriesMultiDeg(TAGGED("Quotient"),WM:MAT):TAGGED("$hp.PSeries")

Description
This function computes the Hilbert-Poincare series of M. The input, M, must be homogeneous with respect to the grading defined by the second argument.

The function PoincareMultiDeg is exacly the same as HilbertSeriesMultiDeg.

NOTES: CoCoA-4 has an intrinsic limitation on multigradings (Weights Modifier) which does not allow zero-entries in the first row of the defining matrix. This function performs all the appropriate conversions for computing the HilbertSeries wrt any positive grading (IsPositiveGrading).

Example
Use R ::= Q[x,y,z];

WM := Mat([[1,0,0],[1,-1,0]]);
HilbertSeriesMultiDeg(R/Ideal(Indets())^2, WM);


See Also