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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 := IntersectionList([ideal(x-1,y-1,z-1), ideal(x-2,y-2)^2, ideal(x)^3]);
/**/ H := $radical.EquiIsoDec(I);  H;
[ideal(x),  ideal(y -2,  x^2 -4*x +4),  ideal(z -1,  x*y -y^2 -2*x +2*y,  x^2 -y^2 -4*x +4*y,  y^3 -5*y^2 +8*y -4)]
/**/ T := [radical(J) | J in H];
/**/ S := IntersectionList(T);
/**/ radical(I) = S;
true

See Also