Package net.hydromatic.morel.util

Class Sat

java.lang.Object

net.hydromatic.morel.util.Sat

public class Sat
extends Object

Boolean satisfiability.

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
(package private) static class	Sat.And	"And" term.
private static class	Sat.Assignment	Assignment of a variable to a value.
(package private) static class	Sat.Node	Term that has a variable number of arguments ("and" or "or").
(package private) static class	Sat.Not	"Not" term.
private static enum	Sat.Op	Operator (or type of term), with its left and right precedence and print name.
(package private) static class	Sat.Or	"Or" term.
static class	Sat.Term	Base class for all terms (variables, and, or, not).
static class	Sat.Variable	Variable.

Field Summary

Fields

Modifier and Type	Field	Description
private int	nextVariable
private final Map<Integer,Sat.Variable>	variablesById
private final Map<String,Sat.Variable>	variablesByName

Constructor Summary

Constructors

Constructor	Description
Sat()

Method Summary

Modifier and Type	Method	Description
Sat.Term	and(Iterable<? extends Sat.Term> terms)
Sat.Term	and(Sat.Term... terms)
Sat.Term	not(Sat.Term term)
Sat.Term	or(Iterable<? extends Sat.Term> terms)
Sat.Term	or(Sat.Term... terms)
@Nullable Map<Sat.Variable,Boolean>	solve(Sat.Term term)	Finds an assignment of variables such that a term evaluates to true, or null if there is no solution.
Sat.Variable	variable(String name)

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Details

variablesById

private final Map<Integer,Sat.Variable> variablesById

variablesByName

private final Map<String,Sat.Variable> variablesByName

nextVariable

private int nextVariable

Constructor Details

Sat

public Sat()

Method Details

solve

public @Nullable Map<Sat.Variable,Boolean> solve(Sat.Term term)

Finds an assignment of variables such that a term evaluates to true, or null if there is no solution.

variable

public Sat.Variable variable(String name)

not

public Sat.Term not(Sat.Term term)

and

public Sat.Term and(Sat.Term... terms)

and

public Sat.Term and(Iterable<? extends Sat.Term> terms)

or

public Sat.Term or(Sat.Term... terms)

or

public Sat.Term or(Iterable<? extends Sat.Term> terms)