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JEP is a Java library for parsing and evaluating mathematical expressions.
/* @author rich
* Created on 09-Mar-2004
*/
package org.lsmp.djep.groupJep.groups;
import org.lsmp.djep.groupJep.interfaces.*;
import org.lsmp.djep.groupJep.values.*;
import org.nfunk.jep.type.*;
/**
* An Algebraic Extension of a Ring.
* The ring generated by {1,t,...,t^n-1} where t is an algebraic number
* i.e t is be a root of a monic polynomial equation.
*
* @see AlgebraicExtensionElement
* @author Rich Morris
* Created on 09-Mar-2004
*/
public class AlgebraicExtension extends ExtendedFreeGroup implements RingI {
private Polynomial poly;
private Polynomial poly2;
/**
* Create the ring K(t) where t is a solution of the monic polynomial p.
*
* @param K the Ring this is an extension of.
* @param poly A monic polynomial whose solution gives an algebraic number which is used to generate this group.
* @throws IllegalArgumentException if the base ring of the poly is not the same.
* @throws IllegalArgumentException if the polynomial is not monic.
*/
public AlgebraicExtension(RingI K, Polynomial poly) {
super(K,poly.getSymbol());
this.poly = poly;
if(baseRing != poly.getBaseRing())
throw new IllegalArgumentException("The polynomial should be specified over the same base ring");
// test for monic
if(!baseRing.equals(
poly.getCoeffs()[poly.getDegree()],
baseRing.getONE()))
throw new IllegalArgumentException("poly "+poly.toString()+" should be monic");
// construct q = t^n - poly (deg n-1)
Number coeffs[] = new Number[poly.getDegree()];
for(int i=0;i