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///////////////////////////////////////////////////////////////////////////////
// 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.data;
import edu.cmu.tetrad.graph.Node;
import edu.cmu.tetrad.util.StatUtils;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
/**
* Model for a conditional histogram for mixed continuous and discrete variables.
*
* @author josephramsey
* @version $Id: $Id
*/
public class Histogram {
private final DataSet dataSet;
private final boolean removeZeroPointsPerPlot;
private Node target;
private int numBins = 10;
private Map continuousIntervals;
private Map discreteValues;
/**
* This histogram is for variables in a particular data set. These may be continuous or discrete.
*
* @param dataSet a {@link edu.cmu.tetrad.data.DataSet} object
* @param target a {@link java.lang.String} object
* @param removeZeroPointsPerPlot a boolean
*/
public Histogram(DataSet dataSet, String target, boolean removeZeroPointsPerPlot) {
if (dataSet.getVariables().size() < 1) {
throw new IllegalArgumentException("Can't do histograms for an empty data sets.");
}
this.dataSet = dataSet;
this.removeZeroPointsPerPlot = removeZeroPointsPerPlot;
setTarget(target);
}
/**
* Adds a continuous conditioning variables, conditioning on a range of values.
*
* @param variable The name of the variable in the data set.
* @param low The low end of the conditioning range.
* @param high The high end of the conditioning range.
*/
public void addConditioningVariable(String variable, double low, double high) {
if (!(low < high)) throw new IllegalArgumentException("Low must be less than high: " + low + " >= " + high);
Node node = this.dataSet.getVariable(variable);
if (!(node instanceof ContinuousVariable)) throw new IllegalArgumentException("Variable must be continuous.");
if (this.continuousIntervals.containsKey(node))
throw new IllegalArgumentException("Please remove conditioning variable first.");
this.continuousIntervals.put(node, new double[]{low, high});
}
/**
* Adds a discrete conditioning variable, conditioning on a particular value.
*
* @param variable The name of the variable in the data set.
* @param value The value to condition on.
*/
public void addConditioningVariable(String variable, int value) {
Node node = this.dataSet.getVariable(variable);
// if (node == this.target) throw new IllegalArgumentException("Conditioning node may not be the target.");
if (!(node instanceof DiscreteVariable)) throw new IllegalArgumentException("Variable must be discrete.");
this.discreteValues.put(node, value);
}
/**
* Removes a conditioning variable.
*
* @param variable The name of the conditioning variable to remove.
*/
public void removeConditioningVariable(String variable) {
Node node = this.dataSet.getVariable(variable);
// if (node == this.target) throw new IllegalArgumentException("The target cannot be a conditioning node.");
if (!(this.continuousIntervals.containsKey(node) || this.discreteValues.containsKey(node))) {
throw new IllegalArgumentException("Not a conditioning node: " + variable);
}
this.continuousIntervals.remove(node);
this.discreteValues.remove(node);
}
/**
* For a continuous target, sets the number of bins for the histogram.
*
* @param numBins The number of bins.
*/
public void setNumBins(int numBins) {
if (this.target instanceof DiscreteVariable) {
throw new IllegalArgumentException("Can't set number of bins for a discrete target.");
}
this.numBins = numBins;
}
/**
* getFrequencies.
*
* @return the counts for the histogram, one count for each target, in an integer array.
*/
public int[] getFrequencies() {
if (this.target instanceof ContinuousVariable) {
List _data = getConditionedDataContinuous();
_data = removeZeroPointsPerPlot(_data);
double[] breakpoints = getBreakpoints(_data, this.numBins);
int[] counts = new int[this.numBins];
for (Double d : _data) {
boolean sorted = false;
int h;
for (h = 0; h < breakpoints.length; h++) {
if (breakpoints[h] > d) {
counts[h]++;
sorted = true;
break;
}
}
if (!sorted) {
counts[breakpoints.length]++;
}
}
return counts;
} else if (this.target instanceof DiscreteVariable _var) {
List _data = getConditionedDataDiscrete();
int[] counts = new int[_var.getNumCategories()];
for (Integer d : _data) {
counts[d]++;
}
return counts;
} else {
throw new IllegalArgumentException("Unrecognized variable type.");
}
}
private List removeZeroPointsPerPlot(List data) {
List _data = new ArrayList<>();
for (double d : data) {
if (!removeZeroPointsPerPlot || d != 0) {
_data.add(d);
}
}
return _data;
}
/**
* For a continuous target, returns the maximum value of the values histogrammed, for the unconditioned data.
*
* @return a double
*/
public double getMax() {
List conditionedDataContinuous = getUnconditionedDataContinuous();
double[] d = asDoubleArray(conditionedDataContinuous);
return StatUtils.max(d);
}
/**
* For a continuous target, returns the minimum value of the values histogrammed, for the unconditioned data.
*
* @return a double
*/
public double getMin() {
List conditionedDataContinuous = getUnconditionedDataContinuous();
double[] d = asDoubleArray(conditionedDataContinuous);
return StatUtils.min(d);
}
/**
* For a continuous target, returns the number of values histogrammed. This may be less than the sample size of the
* data set because of conditioning.
*
* @return a int
*/
public int getN() {
List conditionedDataContinuous = getConditionedDataContinuous();
return conditionedDataContinuous.size();
}
/**
* A convenience method to return the data for a particular named continuous variable.
*
* @param variable The name of the variable.
* @return an array of {@link double} objects
*/
public double[] getContinuousData(String variable) {
int index = this.dataSet.getColumn(this.dataSet.getVariable(variable));
List _data = new ArrayList<>();
for (int i = 0; i < this.dataSet.getNumRows(); i++) {
_data.add(this.dataSet.getDouble(i, index));
}
return asDoubleArray(_data);
}
/**
* Getter for the field dataSet.
*
* @return the data set for this histogram.
*/
public DataSet getDataSet() {
return this.dataSet;
}
/**
* Getter for the field target.
*
* @return the target node being histogrammed. Could be continuous or discrete.
*/
public String getTarget() {
return this.target.getName();
}
/**
* Sets the target. Setting the target removes all conditioning variables and sets the number of bins to the default
* (using Sturges' formula).
*
* @param target The name of the target in the data set.
*/
private void setTarget(String target) {
Node _target;
if (target == null) {
_target = this.dataSet.getVariable(0);
} else {
_target = this.dataSet.getVariable(target);
}
this.target = _target;
this.continuousIntervals = new HashMap<>();
this.discreteValues = new HashMap<>();
// this.numBins = (int) ceil(log(this.dataSet.getNumRows()) / log(2) + 1);
}
/**
* getTargetNode.
*
* @return a {@link edu.cmu.tetrad.graph.Node} object
*/
public Node getTargetNode() {
return this.target;
}
private double[] getBreakpoints(List data, int numBins) {
double[] _data = asDoubleArray(data);
if (data.isEmpty()) throw new IllegalArgumentException("No data.");
double max = StatUtils.max(_data);
double min = StatUtils.min(_data);
double interval = (max - min) / numBins;
double[] breakpoints = new double[numBins - 1];
for (int g = 0; g < numBins - 1; g++) {
breakpoints[g] = min + (g + 1) * interval;
}
return breakpoints;
}
private double[] asDoubleArray(List data) {
double[] _data = new double[data.size()];
for (int i = 0; i < data.size(); i++) _data[i] = data.get(i);
return _data;
}
private List getUnconditionedDataContinuous() {
int index = this.dataSet.getColumn(this.target);
List _data = new ArrayList<>();
for (int i = 0; i < this.dataSet.getNumRows(); i++) {
_data.add(this.dataSet.getDouble(i, index));
}
return _data;
}
private List getConditionedDataContinuous() {
List rows = getConditionedRows();
int index = this.dataSet.getColumn(this.target);
List _data = new ArrayList<>();
for (Integer row : rows) {
_data.add(this.dataSet.getDouble(row, index));
}
return _data;
}
private List getConditionedDataDiscrete() {
List rows = getConditionedRows();
int index = this.dataSet.getColumn(this.target);
List _data = new ArrayList<>();
for (Integer row : rows) {
_data.add(this.dataSet.getInt(row, index));
}
return _data;
}
// Returns the rows in the data that satisfy the conditioning constraints.
private List getConditionedRows() {
List rows = new ArrayList<>();
I:
for (int i = 0; i < this.dataSet.getNumRows(); i++) {
for (Node node : this.continuousIntervals.keySet()) {
double[] range = this.continuousIntervals.get(node);
int index = this.dataSet.getColumn(node);
double value = this.dataSet.getDouble(i, index);
if (!(value >= range[0] && value <= range[1])) {
continue I;
}
}
for (Node node : this.discreteValues.keySet()) {
int value = this.discreteValues.get(node);
int index = this.dataSet.getColumn(node);
int _value = this.dataSet.getInt(i, index);
if (!(value == _value)) {
continue I;
}
}
rows.add(i);
}
return rows;
}
}