org.uacalc.alg
Interface SmallAlgebra

All Superinterfaces:

Algebra

All Known Implementing Classes:

BasicAlgebra, BasicLattice, FreeAlgebra, PolinLikeAlgebra, PowerAlgebra, ProductAlgebra, QuotientAlgebra, ReductAlgebra, Subalgebra, SubProductAlgebra, UnaryTermsMonoid

public interface SmallAlgebra
extends Algebra

A small algebra is one whose universe can be effectively indexed by {0,..., n-1} for some positive int n. cardinality() should return n.

Version:

$Id: SmallAlgebra.java,v 1.6 2008/07/22 04:28:20 ralphfreese Exp $

Author:

Ralph Freese

Nested Class Summary

static class

SmallAlgebra.AlgebraType

Field Summary

Fields inherited from interface org.uacalc.alg.Algebra

CARDINALITY_COUNTABLE, CARDINALITY_COUNTABLY_INFINITE, CARDINALITY_FINITE, CARDINALITY_INFINITE, CARDINALITY_UNKNOWN

Method Summary

SmallAlgebra.AlgebraType	algebraType() The type of algebra this is, like a quotient algebra.
CongruenceLattice	con() The congurence lattice.
void	convertToDefaultValueOps() This is used in the UI.
int	elementIndex(java.lang.Object elem) This method will return k if elem is the kth element; otherwise -1.
java.lang.Object	getElement(int k) returns the kth element.
java.util.List	getUniverseList() The universe as a List such getElement(k) will equal the kth element of the List.
java.util.Map	getUniverseOrder() A map that can be used for elementIndex(a).
SmallAlgebra	parent() For a BasicAlgebra this is null; for a QuotientAlgebra this is the preimage; for a Subalgebra it is the super algebra.
java.util.List<SmallAlgebra>	parents() For a ProductAlgebra this will be the factors.
void	resetConAndSub()
SubalgebraLattice	sub() The subalgebra lattice.

Methods inherited from interface org.uacalc.alg.Algebra

cardinality, constantOperations, getDescription, getMonitor, getName, getOperation, getOperationsMap, inputSize, isIdempotent, isSimilarTo, isTotal, isUnary, iterator, makeOperationTables, monitoring, operations, setDescription, setMonitor, setName, similarityType, universe

Method Detail

algebraType

SmallAlgebra.AlgebraType algebraType()

The type of algebra this is, like a quotient algebra.

Returns:

getElement

java.lang.Object getElement(int k)

returns the kth element.

elementIndex

int elementIndex(java.lang.Object elem)

This method will return k if elem is the kth element; otherwise -1. (Should we have it throw an error instead?)

getUniverseList

java.util.List getUniverseList()

The universe as a List such getElement(k) will equal the kth element of the List. It is allowed to be null.

getUniverseOrder

java.util.Map getUniverseOrder()

A map that can be used for elementIndex(a). It is allowed to be null.

con

CongruenceLattice con()

The congurence lattice.

sub

SubalgebraLattice sub()

The subalgebra lattice.

resetConAndSub

void resetConAndSub()

parent

SmallAlgebra parent()

For a BasicAlgebra this is null; for a QuotientAlgebra this is the preimage; for a Subalgebra it is the super algebra.

parents

java.util.List<SmallAlgebra> parents()

For a ProductAlgebra this will be the factors. For a BasicAlgebra it will be null. Otherwise it is a list of the parent algebra.

See Also:

parent

convertToDefaultValueOps

void convertToDefaultValueOps()

This is used in the UI. Only valid for BASIC algebras.