net.sourceforge.czt.animation.eval.flatpred

Class FlatPowerSet

java.lang.Object

net.sourceforge.czt.animation.eval.flatpred.FlatPred

net.sourceforge.czt.animation.eval.flatpred.FlatPowerSet

public class FlatPowerSet
extends FlatPred

Author:

Mark Utting FlatPowerSet(base,set) implements \power base = set. It is capable of checking that a given finite set is a member of the powerset (it does this by iterating through its elements) and of generating all elements of the powerset when the base set is small (<= 30).

Field Summary

Fields inherited from class net.sourceforge.czt.animation.eval.flatpred.FlatPred

args_, evalMode_, freeVars_, INDENT, LOG, printer_, solutionsReturned_

Constructor Summary

Constructors

Constructor and Description
FlatPowerSet(net.sourceforge.czt.z.ast.ZName baseSet, net.sourceforge.czt.z.ast.ZName set) Creates a FlatPowerSet object.

Method Summary

Modifier and Type	Method and Description
<R> R	accept(net.sourceforge.czt.util.Visitor<R> visitor) Calls visitor.visitPred (preferably) or visitor.visitTerm.
Mode	chooseMode(Envir env) Chooses the mode in which the predicate can be evaluated.
boolean	inferBounds(Bounds bnds) Adds this power set into the Bounds information.
boolean	nextEvaluation() Does the actual evaluation
Iterator<net.sourceforge.czt.z.ast.Expr>	subsetIterator(net.sourceforge.czt.z.ast.ZName element)
String	toString() A default implementation of toString.

Methods inherited from class net.sourceforge.czt.animation.eval.flatpred.FlatPred

freeVars, getArgs, getEnvir, getLastArg, getMode, indent, modeAllDefined, modeCollection, modeFunction, modeOneOutput, printArg, printBinOp, printLastArg, printName, printQuant, setMode, startEvaluation

Methods inherited from class java.lang.Object

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

Constructor Detail

FlatPowerSet

public FlatPowerSet(net.sourceforge.czt.z.ast.ZName baseSet,
                    net.sourceforge.czt.z.ast.ZName set)

Creates a FlatPowerSet object.

Parameters:

baseSet - the underlying set, from which all subsets will be taken.

set - the name of the resulting set of subsets.

Method Detail

inferBounds

public boolean inferBounds(Bounds bnds)

Adds this power set into the Bounds information.

Overrides:

inferBounds in class FlatPred

Parameters:

bnds - The database of lower and upper bounds for integer variables.

Returns:

true iff the bnds database has been changed.

The default implementation infers nothing and returns false.

chooseMode

public Mode chooseMode(Envir env)

Chooses the mode in which the predicate can be evaluated.

Specified by:

chooseMode in class FlatPred

Returns:

The Mode object, with statistics and an updated environment.

nextEvaluation

public boolean nextEvaluation()

Does the actual evaluation

Specified by:

nextEvaluation in class FlatPred

Returns:

true iff another solution has been found.

toString

public String toString()

Description copied from class: FlatPred

A default implementation of toString. This returns "FlatXXX(args[0], args[1], ...)".

Overrides:

toString in class FlatPred

accept

public <R> R accept(net.sourceforge.czt.util.Visitor<R> visitor)

Description copied from class: FlatPred

Calls visitor.visitPred (preferably) or visitor.visitTerm. Subclasses that correspond to particular kinds of Pred should override this to call more specific visitXXX methods (and should call super to handle the remaining cases).

Overrides:

accept in class FlatPred

subsetIterator

public Iterator<net.sourceforge.czt.z.ast.Expr> subsetIterator(net.sourceforge.czt.z.ast.ZName element)