edu.cmu.tetrad.search.utils.SepsetMap Maven / Gradle / Ivy
///////////////////////////////////////////////////////////////////////////////
// For information as to what this class does, see the Javadoc, below. //
// Copyright (C) 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, //
// 2007, 2008, 2009, 2010, 2014, 2015, 2022 by Peter Spirtes, Richard //
// Scheines, Joseph Ramsey, and Clark Glymour. //
// //
// This program is free software; you can redistribute it and/or modify //
// it under the terms of the GNU General Public License as published by //
// the Free Software Foundation; either version 2 of the License, or //
// (at your option) any later version. //
// //
// This program is distributed in the hope that it will be useful, //
// but WITHOUT ANY WARRANTY; without even the implied warranty of //
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the //
// GNU General Public License for more details. //
// //
// You should have received a copy of the GNU General Public License //
// along with this program; if not, write to the Free Software //
// Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA //
///////////////////////////////////////////////////////////////////////////////
package edu.cmu.tetrad.search.utils;
import edu.cmu.tetrad.graph.Node;
import edu.cmu.tetrad.util.TetradSerializable;
import java.io.IOException;
import java.io.ObjectInputStream;
import java.util.*;
import java.util.concurrent.ConcurrentHashMap;
/**
* Stores a map from pairs of nodes to separating sets--that is, for each unordered pair of nodes {node1, node2} in
* a graph, stores a set of nodes conditional on which node1 and node2 are independent (where the nodes are considered
* as variables) or stores null if the pair was not judged to be independent. (Note that if a sepset is non-null and
* empty, that should mean that the compared nodes were found to be independent conditional on the empty set, whereas if
* a sepset is null, that should mean that no set was found yet conditional on which the compared nodes are independent.
* So at the end of the search, a null sepset carries different information from an empty sepset.)> 0
We cast the
* variable-like objects to Node to allow them either to be variables explicitly or else to be graph nodes that in some
* model could be considered as variables. This allows us to use d-separation as a graphical indicator of what
* independence in models ideally should be.> 0
*
* @author josephramsey
*/
public final class SepsetMap implements TetradSerializable {
private static final long serialVersionUID = 23L;
private final Map> parents = new HashMap<>();
private Map, Set> sepsets = new ConcurrentHashMap<>();
private Map, Double> pValues = new ConcurrentHashMap<>();
/**
* Constructor.
*/
public SepsetMap() {
}
/**
* Copy constructor.
*
* @param map A given sepset map.
*/
public SepsetMap(SepsetMap map) {
this.sepsets = new HashMap<>(map.sepsets);
this.pValues = new HashMap<>(map.pValues);
}
/**
* Generates a simple exemplar of this class to test serialization.
*/
public static SepsetMap serializableInstance() {
return new SepsetMap();
}
/**
* Sets the sepset for {x, y} to be z. Note that {x, y} is unordered.
*/
public void set(Node x, Node y, Set z) {
Set pair = new HashSet<>(2);
pair.add(x);
pair.add(y);
if (z == null) {
this.sepsets.remove(pair);
} else {
this.sepsets.put(pair, z);
}
}
/**
* Retrieves the sepset previously set for {a, b}, or null if no such set was previously set.
*/
public Set get(Node a, Node b) {
Set pair = new HashSet<>(2);
pair.add(a);
pair.add(b);
return this.sepsets.get(pair);
}
/**
* Looks up the p-value for {x, y}
*/
public double getPValue(Node x, Node y) {
Set pair = new HashSet<>(2);
pair.add(x);
pair.add(y);
return this.pValues.get(pair);
}
/**
* Sets the parents of x to the (ordered) set z.
*/
public void set(Node x, LinkedHashSet z) {
if (this.parents.get(x) != null) {
this.parents.get(x).addAll(z);
} else {
this.parents.put(x, z);
}
}
/**
* Returns the parents of the node x.
*/
public HashSet get(Node x) {
return this.parents.get(x) == null ? new HashSet<>() : this.parents.get(x);
}
/**
* Checks equality of this to another sepset map.
*/
public boolean equals(Object o) {
if (o == null) {
return false;
}
if (!(o instanceof SepsetMap)) {
return false;
}
SepsetMap _sepset = (SepsetMap) o;
return this.sepsets.equals(_sepset.sepsets);
}
/**
* Adds semantic checks to the default deserialization method. This method must have the standard signature for a
* readObject method, and the body of the method must begin with "s.defaultReadObject();". Other than that, any
* semantic checks can be specified and do not need to stay the same from version to version. A readObject method of
* this form may be added to any class, even if Tetrad sessions were previously saved out using a version of the
* class that didn't include it. (That's what the "s.defaultReadObject();" is for. See J. Bloch, Effective Java, for
* help).
*/
private void readObject(ObjectInputStream s)
throws IOException, ClassNotFoundException {
s.defaultReadObject();
if (this.sepsets == null) {
throw new NullPointerException();
}
}
/**
* Returns the number of {x, y} in the key set of the map.
*/
public int size() {
return this.sepsets.keySet().size();
}
/**
* Returns a string representation of this sepset map.
*/
public String toString() {
return this.sepsets.toString();
}
/**
* Adds all entries in the given sepset map to the current one.
*/
public void addAll(SepsetMap newSepsets) {
this.sepsets.putAll(newSepsets.sepsets);
}
}