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 IntersectionList

intersect lists, ideals, or modules
 Syntax
 ``` IntersectionList(L:LIST of LIST):LIST IntersectionList(L:LIST of IDEAL):IDEAL IntersectionList(L:LIST of MODULE):MODULE ```

 Description
The function IntersectionList applies the function Intersection to the elements of a list, i.e., IntersectionList([X_1,...,X_n]) is the same as Intersection(X_1,...,X_n).

The coefficient ring must be a field.

NOTE: In order to compute the intersection of inhomogeneous ideals, it may be faster to use the function HIntersectionList.

To compute the intersection of ideals corresponding to zero-dimensional schemes, see the commands GBM and HGBM .

 Example
 ``` Use R ::= QQ[x,y,z]; Points := [[0,0],[1,0],[0,1],[1,1]]; -- a list of points in the plane IntersectionList([ Ideal(x-P[1]z, y-P[2]z) | P In Points]); Ideal(y^2 - yz, x^2 - xz) ------------------------------- Intersection(["a","b","c"],["b","c","d"]); ["b", "c"] ------------------------------- IntersectionList([Ideal(x,y), Ideal(y^2,z)]); Ideal(yz, xz, y^2) ------------------------------- It = Intersection(Ideal(x,y), Ideal(y^2,z)); TRUE ------------------------------- ```