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EquiIsoDec

equidimensional isoradical decomposition
Syntax 

EquiIsoDec(I:IDEAL):LIST of IDEAL

Description
This function computes an equidimensional isoradical decomposition of I, i.e. a list of unmixed ideals I_1,...,I_k such that the radical of I is the intersection of the radicals of I_1,...,I_k. Redundancies are possible.

NOTE: at the moment, this implementation works only if the coefficient ring is the rationals or has large enough characteristic.

Example 
  Use R ::= QQ[x,y,z];
  I := Intersection(Ideal(x-1,y-1,z-1), Ideal(x-2,y-2)^2, Ideal(x)^3);
  H := EquiIsoDec(I);
  H;
[Ideal(x), Ideal(z - 1, y - 1, x - 1), Ideal(xy - y^2 - 2x + 2y, x^2 -
y^2 - 4x + 4y, y^2z - y^2 - 4yz + 4y + 4z - 4, y^3 - 5y^2 + 8y - 4, x
- 2)]
-------------------------------
  T := [Radical(J)|J In H];
  S := IntersectionList(T);
  Radical(I) = S;
TRUE
-------------------------------


See Also