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ideal

convert an expression into an ideal

Syntax
Ideal(P_1:POLY,...,P_n:POLY):IDEAL
Ideal(L:LIST):IDEAL
Ideal(M:MODULE):IDEAL

where L is a list of polynomials and M is contained in a free module
of rank 1.

Description
The first form returns the ideal generated by P_1,...P_n . The second form returns the ideal generated by the polynomials in L. The third form returns the ideal generated by the polynomials in M; it is the same as Cast(M, IDEAL) , and requires that the module be a submodule of the free module of rank 1.

Example
/**/  Use R ::= QQ[x,y,z];
/**/  I := ideal(x-y^2, x*y-z);
/**/  I;
ideal(-y^2 +x, x*y -z)

/**/  L := [x*y-z, x-y^2];
/**/  J := ideal(L);
/**/  I = J;
true

/**/  M := Module([y^3-z],[x-y^2]);  --***OBSOLETE MANUAL: WORK IN PROGRESS***
/**/  ideal(M) = I;
true