CoCoA:Minimalized

From ApCoCoAWiki

Minimalized

remove redundant generators

Description

In the inhomogeneous case it returns the ideal or module

obtained by removing redundant generators from E.

In the homogeneous case, it obtains a generating set with smallest

possible cardinality. The minimal set of generators found by CoCoA is

not necessarily a subset of the given generators. It returns the minimalized ideal or module.

The coefficient ring is assumed to be a field.

The similar function <ttref>Minimalize</ttref> performs the same

operation, but modifies the argument and returns NULL.

Example

  Use R ::= Q[x,y,z];
  I := Ideal(x-y^2,z-y^5,x^5-z^2);
  I;
Ideal(-y^2 + x, -y^5 + z, x^5 - z^2)
-------------------------------
  Minimalized(I);
Ideal(-y^2 + x, -y^5 + z)
-------------------------------
  I;
Ideal(-y^2 + x, -y^5 + z, x^5 - z^2)
-------------------------------
  Minimalize(I);
I;
Ideal(-y^2 + x, -y^5 + z)
-------------------------------
  J := Ideal(x, x-y, y-z, z^2);
  Minimalized(J);
Ideal(y - z, x - z, z)
-------------------------------

Syntax

Minimalized(E:IDEAL):IDEAL
Minimalized(E:MODULE):MODULE

where X is a variable containing an ideal or module.

MinGens

Minimalize

   <type>ideal</type>
   <type>module</type>