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TVecFromHF    --    Type vector from Hilbert Function


Syntax 
TVecFromHF(H: TAGGED): LIST
TVecFromHF(H: LIST): LIST

Description
This function returns a LIST representing the type vector corresponding to the Hilbert function H.

This is part of the CoCoA package TypeVectors originally by E.Carlini, M.Stewart for computing with type vectors as described in A.Geramita, T.Harima, Y.Shin An alternative to the Hilbert function for the ideal of a finite set of points in P^n Illinois J.Math. vol.45 (2001), no. 1, pages 1--23.

Example 
/**/  Use P ::= QQ[x,y,z,t];
/**/  HF := HilbertFn(P/Ideal(x, y^3, z^2-t*x));  HF;
/**/  TV := TVecFromHF(HF);  TV;
[[[2],  [4]]]
/**/  TV := TVecFromHF([[1, 3, 5], 6]);  TV;
[[[2],  [4]]]

See Also