BasicVar.html

BasicVar.java

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package blog;

import java.util.*;

import common.Util;

A basic random variable in a BLOG model. A BasicVar is a BayesNetVar whose value is stored explicitly in a PossibleWorld. The set of basic variables is defined implicitly by a BLOG model. BasicVar objects are just a convenience for bundling together a function and a tuple of arguments, or a POP and a tuple of generating objects.


public abstract class BasicVar implements BayesNetVar, Comparable, Cloneable {

Creates a new BasicVar with the given tuple of arguments or generating objects.


    protected BasicVar(Object[] args) {
	this.args = args;
    }

Creates a new BasicVar with the given tuple of arguments or generating objects. If stable is true, then the caller guarantees that the given args array will not be modified externally.


    protected BasicVar(Object[] args, boolean stable) {
	this.args = args;
	this.stable = stable;
    }

Creates a new BasicVar with the given tuple of arguments or generating objects.


    protected BasicVar(List argList) {
	args = new Object[argList.size()];
	argList.toArray(args);
	stable = true;
    }

Returns the tuple of arguments if this is a function application variable, or the tuple of generating objects if this is a number variable. The returned array should not be modified.


    public final Object[] args() {
	return args;
    }

Returns the type of object that can be a value for this variable.


    public abstract Type getType();

Returns an index to be used for comparing this variable to others. Variables for which this method returns the same index value will be compared based on their arguments.


    public abstract int getOrderingIndex();

A basic random variable is determined if and only if it is instantiated.


    public boolean isDetermined(PartialWorld w) {
	return (w.getValue(this) != null);
    }

Returns the value of this basic variable in the given world.


    public Object getValue(PartialWorld w) {
	return w.getValue(this);
    }

Returns a term whose value in any possible world is the same as this random variable's value.


    public FuncAppTerm getCanonicalTerm() {
	return getCanonicalTerm(Collections.EMPTY_MAP);
    }

Returns a term whose value in any possible world is the same as this random variable's value, assuming that objects are bound to logical variables as specified in logicalVarForObj.

Parameters:

logicalVarForObj - map from Object to LogicalVar


    public FuncAppTerm getCanonicalTerm(Map logicalVarForObj) {
	throw new UnsupportedOperationException
	    ("Can't convert random variable to term: " + this);
    }

Ensures that this BasicVar's arguments are stored in an array that will not be modified externally.


    public void ensureStable() {
	if (!stable) {
	    args = (Object[]) args.clone();
	    stable = true;
	}
    }

    public Timestep timestep() {
	Timestep ret = null;
	for (int i = 0; i < args.length; ++i) {
	    if (args[i] instanceof Timestep) {
		if (ret != null) {
		    Util.fatalError("Random variable " + this 
				    + " depends on more than one timestep.");
		}
		ret = (Timestep) args[i];
	    }
	}
	return ret;
    }

Compares this BasicVar to another one. The ordering is intended to be used for printing basic variables. First, basic variables are compared based on the order in which their dependency models were created; this corresponds to the order of definition in the model file. For basic variables with the same dependency model, we use a lexicographic ordering based on the arguments.


    public int compareTo(Object o) {
	BasicVar other = (BasicVar) o;
	int indexDiff = getOrderingIndex() - other.getOrderingIndex(); 
	if (indexDiff != 0) {
	    return indexDiff;
	}

	return Model.compareArgTuples(args, other.args());
    }

    public abstract Object clone();

    protected Object[] args; // of Object

    private boolean stable = false;
}

This file was generated on Tue Jun 08 17:53:36 PDT 2010 from file BasicVar.java
by the ilog.language.tools.Hilite Java tool written by Hassan Aït-Kaci