net.sourceforge.czt.animation.eval.flatpred

Class Mode

java.lang.Object

net.sourceforge.czt.animation.eval.flatpred.Mode

Direct Known Subclasses:

ModeList

public class Mode
extends Object

A Mode object contains information about one way of executing a FlatPred. It contains statistics about the number of solutions expected when the FlatPred is executed, plus an updated environment which contains any variables created by the FlatPred.

Author:

marku

Field Summary

Fields

Modifier and Type	Field and Description
protected List<net.sourceforge.czt.z.ast.ZName>	args_ A copy of the arguments of this FlatPred.
static double	MAYBE_ONE_SOLUTION A constant for getSolutions().
static double	ONE_SOLUTION A constant for getSolutions().
protected int	outputs_ The number of output variables.
protected FlatPred	parent_
protected Envir	postEnvir_ The environment after executing the FlatPred.
protected Envir	preEnvir_ The environment before executing the FlatPred.
protected double	solutions_ The expected number of solutions.

Constructor Summary

Constructors

Constructor and Description
Mode(FlatPred parent, Envir preEnv, List<net.sourceforge.czt.z.ast.ZName> args, double solns) Constructor for Mode objects.

Method Summary

Modifier and Type	Method and Description
boolean	compatible(Mode other) Two modes are compatible if they have the same outputs.
Envir	getEnvir() Get the environment that includes any output variables of FlatPred.
Envir	getEnvir0() Get the input environment of this Mode.
Set<net.sourceforge.czt.z.ast.ZName>	getOutputs() Gives the variables added to the environment by this mode.
FlatPred	getParent() Returns the FlatPred that created this mode
double	getSolutions() The estimated number of solutions that the FlatPred will produce.
boolean	isInput(int pos) A convenience version of isInput that takes the position of the variable in the FlatPred getArgs() list.
boolean	isInput(net.sourceforge.czt.z.ast.ZName arg) Is the given argument an input?
boolean	isOutput(net.sourceforge.czt.z.ast.ZName arg) Is the given argument an output?
int	numOutputs() Gives the number of output variables.
void	setSolutions(double solns) Set the estimated number of solutions the FlatPred will produce.
String	toString()

Methods inherited from class java.lang.Object

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

Field Detail

ONE_SOLUTION

public static final double ONE_SOLUTION

A constant for getSolutions(). Means that one solution is expected.

See Also:

Constant Field Values

MAYBE_ONE_SOLUTION

public static final double MAYBE_ONE_SOLUTION

A constant for getSolutions(). Means that zero or one solutions are expected.

See Also:

Constant Field Values

solutions_

protected double solutions_

The expected number of solutions.

preEnvir_

protected Envir preEnvir_

The environment before executing the FlatPred.

postEnvir_

protected Envir postEnvir_

The environment after executing the FlatPred.

args_

protected List<net.sourceforge.czt.z.ast.ZName> args_

A copy of the arguments of this FlatPred. These are just saved for convenience, so that we can provide the isInput(int) method.

outputs_

protected int outputs_

The number of output variables.

parent_

protected FlatPred parent_

Constructor Detail

Mode

public Mode(FlatPred parent,
            Envir preEnv,
            List<net.sourceforge.czt.z.ast.ZName> args,
            double solns)

Constructor for Mode objects.

Method Detail

getParent

public FlatPred getParent()

Returns the FlatPred that created this mode

isInput

public boolean isInput(net.sourceforge.czt.z.ast.ZName arg)

Is the given argument an input?

isInput

public boolean isInput(int pos)

A convenience version of isInput that takes the position of the variable in the FlatPred getArgs() list.

isOutput

public boolean isOutput(net.sourceforge.czt.z.ast.ZName arg)

Is the given argument an output?

getSolutions

public double getSolutions()

The estimated number of solutions that the FlatPred will produce. The result will always be positive. It is an approximation of how many solutions the FlatPred is likely to generate in this mode. For example, 1.0 means exactly one solution is expected, 100 means that around 100 solutions are expected, and 0.5 means that 0 or 1 solutions are expected.

setSolutions

public void setSolutions(double solns)

Set the estimated number of solutions the FlatPred will produce.

getEnvir0

public Envir getEnvir0()

Get the input environment of this Mode.

getEnvir

public Envir getEnvir()

Get the environment that includes any output variables of FlatPred.

getOutputs

public Set<net.sourceforge.czt.z.ast.ZName> getOutputs()

Gives the variables added to the environment by this mode.

numOutputs

public int numOutputs()

Gives the number of output variables.

toString

public String toString()

Overrides:

toString in class Object

compatible

public boolean compatible(Mode other)

Two modes are compatible if they have the same outputs. However, either side is allowed to have extra tmp* outputs. TODO: check the correctness of this by checking that those extra tmp* outputs do not appear free outside that disjunct. Ideally, the constructor of the FlatOr should remove such names from the freevar set. However, this is not easy to do, because it requires a more global view than the constructor has. Ideally, we should compare just the *free* variables of the two predicates.