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HIntersection, HIntersectionList
Syntax
HIntersection(I_1:IDEAL,...,I_n:IDEAL):IDEAL
HIntersectionList(L:LIST of IDEAL):IDEAL
Summary
intersection of ideals
Description
The function 'HIntersection' returns the intersection of I_1,...,I_n
using a Hilbert-driven algorithm.  It differs from 'Intersection' only
when the input is inhomogeneous, in which case, 'HIntersection'
may be faster.

The function 'HIntersectionList' applies the function 'HIntersection'
to the elements of a list, i.e., 'HIntersectionList([I_1,...,I_n])' is
the same as 'HIntersection(I_1,...,I_n)'.

The coefficient ring must be a field.

Example

Use R ::= Q[x,y,z];
HIntersection(Ideal(x-z,y-2z),Ideal(x-2z,y-z));
Ideal(x + y - 3z, y^2 - 3yz + 2z^2)
-------------------------------
L := [Ideal(x-z,y-2z),Ideal(x-2z,y-z)];
HIntersectionList(L);
Ideal(x + y - 3z, y^2 - 3yz + 2z^2)
-------------------------------
See also: