/*
* Encog(tm) Core v3.3 - Java Version
* http://www.heatonresearch.com/encog/
* https://github.com/encog/encog-java-core
* Copyright 2008-2014 Heaton Research, Inc.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*
* For more information on Heaton Research copyrights, licenses
* and trademarks visit:
* http://www.heatonresearch.com/copyright
*/
package org.encog.util.arrayutil;
import java.io.Serializable;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import org.encog.Encog;
import org.encog.app.analyst.csv.basic.BasicFile;
import org.encog.app.quant.QuantError;
import org.encog.mathutil.Equilateral;
import org.encog.util.EngineArray;
import org.encog.util.csv.CSVFormat;
/**
* This object holds the normalization stats for a column. This includes the
* actual and desired high-low range for this column.
*/
public class NormalizedField implements Serializable {
/**
* The actual high from the sample data.
*/
private double actualHigh;
/**
* The actual low from the sample data.
*/
private double actualLow;
/**
* The desired normalized high.
*/
private double normalizedHigh;
/**
* The desired normalized low from the sample data.
*/
private double normalizedLow;
/**
* The action that should be taken on this column.
*/
private NormalizationAction action;
/**
* The name of this column.
*/
private String name;
/**
* The list of classes.
*/
private final List<ClassItem> classes = new ArrayList<ClassItem>();
/**
* If equilateral classification is used, this is the Equilateral object.
*/
private Equilateral eq;
/**
* Allows the index of a field to be looked up.
*/
private final Map<String, Integer> lookup = new HashMap<String, Integer>();
/**
* Construct the object with a range of 1 and -1.
*/
public NormalizedField() {
this(1, -1);
}
/**
* Construct the object.
*
* @param theNormalizedHigh
* The normalized high.
* @param theNormalizedLow
* The normalized low.
*/
public NormalizedField(final double theNormalizedHigh,
final double theNormalizedLow) {
this.normalizedHigh = theNormalizedHigh;
this.normalizedLow = theNormalizedLow;
this.actualHigh = Double.MIN_VALUE;
this.actualLow = Double.MAX_VALUE;
this.action = NormalizationAction.Normalize;
}
/**
* Construct an object.
*
* @param theAction
* The desired action.
* @param theName
* The name of this column.
*/
public NormalizedField(final NormalizationAction theAction,
final String theName) {
this(theAction, theName, 0, 0, 0, 0);
}
/**
* Construct the field, with no defaults.
*
* @param theAction
* The normalization action to take.
* @param theName
* The name of this field.
* @param ahigh
* The actual high.
* @param alow
* The actual low.
* @param nhigh
* The normalized high.
* @param nlow
* The normalized low.
*/
public NormalizedField(final NormalizationAction theAction,
final String theName,
final double ahigh, final double alow, final double nhigh,
final double nlow) {
this.action = theAction;
this.actualHigh = ahigh;
this.actualLow = alow;
this.normalizedHigh = nhigh;
this.normalizedLow = nlow;
this.name = theName;
}
/**
* Construct the object.
* @param theName The name of the field.
* @param theAction The action of the field.
* @param high The high end of the range for the field.
* @param low The low end of the range for the field.
*/
public NormalizedField(final String theName,
final NormalizationAction theAction,
final double high, final double low) {
this.name = theName;
this.action = theAction;
this.normalizedHigh = high;
this.normalizedLow = low;
}
/**
* Analyze the specified value. Adjust min/max as needed. Usually used only
* internally.
*
* @param d
* The value to analyze.
*/
public final void analyze(final double d) {
this.actualHigh = Math.max(this.actualHigh, d);
this.actualLow = Math.min(this.actualLow, d);
}
/**
* Denormalize the specified value.
*
* @param value
* The value to normalize.
* @return The normalized value.
*/
public final double deNormalize(final double value) {
final double result = ((this.actualLow - this.actualHigh) * value
- this.normalizedHigh * this.actualLow + this.actualHigh
* this.normalizedLow)
/ (this.normalizedLow - this.normalizedHigh);
return result;
}
/**
* Determine what class the specified data belongs to.
*
* @param data
* The data to analyze.
* @return The class the data belongs to.
*/
public final ClassItem determineClass(final double[] data) {
int resultIndex = 0;
switch (this.action) {
case Equilateral:
resultIndex = this.eq.decode(data);
break;
case OneOf:
resultIndex = EngineArray.indexOfLargest(data);
break;
case SingleField:
resultIndex = (int) data[0];
break;
default:
throw new QuantError("Unknown action: " + action);
}
return this.classes.get(resultIndex);
}
/**
* Encode the headers used by this field.
* @return A string containing a comma separated list with the headers.
*/
public final String encodeHeaders() {
final StringBuilder line = new StringBuilder();
switch (this.action) {
case SingleField:
BasicFile.appendSeparator(line, CSVFormat.EG_FORMAT);
line.append('\"');
line.append(this.name);
line.append('\"');
break;
case Equilateral:
for (int i = 0; i < this.classes.size() - 1; i++) {
BasicFile.appendSeparator(line, CSVFormat.EG_FORMAT);
line.append('\"');
line.append(this.name);
line.append('-');
line.append(i);
line.append('\"');
}
break;
case OneOf:
for (int i = 0; i < this.classes.size(); i++) {
BasicFile.appendSeparator(line, CSVFormat.EG_FORMAT);
line.append('\"');
line.append(this.name);
line.append('-');
line.append(i);
line.append('\"');
}
break;
default:
return null;
}
return line.toString();
}
/**
* Encode a single field.
*
* @param classNumber
* The class number to encode.
* @return The encoded columns.
*/
public final String encodeSingleField(final int classNumber) {
final StringBuilder result = new StringBuilder();
result.append(classNumber);
return result.toString();
}
/**
* Fix normalized fields that have a single value for the min/max. Separate
* them by 2 units.
*/
public final void fixSingleValue() {
if (this.action == NormalizationAction.Normalize) {
if (Math.abs(this.actualHigh - this.actualLow)
< Encog.DEFAULT_DOUBLE_EQUAL) {
this.actualHigh += 1;
this.actualLow -= 1;
}
}
}
/**
* @return The action for the field.
*/
public final NormalizationAction getAction() {
return this.action;
}
/**
* @return The actual high for the field.
*/
public final double getActualHigh() {
return this.actualHigh;
}
/**
* @return The actual low for the field.
*/
public final double getActualLow() {
return this.actualLow;
}
/**
* @return A list of any classes in this field.
*/
public final List<ClassItem> getClasses() {
return this.classes;
}
/**
* @return Returns the number of columns needed for this classification. The
* number of columns needed will vary, depending on the
* classification method used.
*/
public final int getColumnsNeeded() {
switch (this.action) {
case Ignore:
return 0;
case Equilateral:
return this.classes.size() - 1;
case OneOf:
return this.classes.size();
default:
return 1;
}
}
/**
* @return The equilateral object used by this class, null if none.
*/
public final Equilateral getEq() {
return this.eq;
}
/**
* @return The name of the field.
*/
public final String getName() {
return this.name;
}
/**
* @return The normalized high for the field.
*/
public final double getNormalizedHigh() {
return this.normalizedHigh;
}
/**
* @return The normalized low for the neural network.
*/
public final double getNormalizedLow() {
return this.normalizedLow;
}
/**
* Init any internal structures.
*
*/
public final void init() {
if (this.action == NormalizationAction.Equilateral) {
if (this.classes.size() < Equilateral.MIN_EQ) {
throw new QuantError(
"There must be at least three classes "
+ "to make use of equilateral normalization.");
}
this.eq = new Equilateral(this.classes.size(), this.normalizedHigh,
this.normalizedLow);
}
// build lookup map
for (int i = 0; i < this.classes.size(); i++) {
this.lookup.put(this.classes.get(i).getName(), this.classes.get(i)
.getIndex());
}
}
/**
* @return Is this field a classify field.
*/
public final boolean isClassify() {
// TODO Auto-generated method stub
return (this.action == NormalizationAction.Equilateral)
|| (this.action == NormalizationAction.OneOf)
|| (this.action == NormalizationAction.SingleField);
}
/**
* Lookup the specified field.
*
* @param str
* The name of the field to lookup.
* @return The index of the field, or -1 if not found.
*/
public final int lookup(final String str) {
if (!this.lookup.containsKey(str)) {
return -1;
}
return this.lookup.get(str);
}
/**
* Make a field to hold a class. Use a numeric range for class items.
* @param theAction The action to take.
* @param classFrom The beginning class item.
* @param classTo The ending class item.
* @param high The output high value.
* @param low The output low value.
*/
public final void makeClass(final NormalizationAction theAction,
final int classFrom, final int classTo, final int high,
final int low) {
if ((theAction != NormalizationAction.Equilateral)
&& (theAction != NormalizationAction.OneOf)
&& (theAction != NormalizationAction.SingleField)) {
throw new QuantError("Unsupported normalization type");
}
this.action = theAction;
this.classes.clear();
this.normalizedHigh = high;
this.normalizedLow = low;
this.actualHigh = 0;
this.actualLow = 0;
int index = 0;
for (int i = classFrom; i < classTo; i++) {
this.classes.add(new ClassItem("" + i, index++));
}
}
/**
* Create a field that will be used to hold a class.
* @param theAction The action for this field.
* @param cls The class items.
* @param high The output high value.
* @param low The output low value.
*/
public final void makeClass(final NormalizationAction theAction,
final String[] cls,
final double high, final double low) {
if ((theAction != NormalizationAction.Equilateral)
&& (theAction != NormalizationAction.OneOf)
&& (theAction != NormalizationAction.SingleField)) {
throw new QuantError("Unsupported normalization type");
}
this.action = theAction;
this.classes.clear();
this.normalizedHigh = high;
this.normalizedLow = low;
this.actualHigh = 0;
this.actualLow = 0;
for (int i = 0; i < cls.length; i++) {
this.classes.add(new ClassItem(cls[i], i));
}
}
/**
* Make this a pass-through field.
*/
public final void makePassThrough() {
this.normalizedHigh = 0;
this.normalizedLow = 0;
this.actualHigh = 0;
this.actualLow = 0;
this.action = NormalizationAction.PassThrough;
}
/**
* Normalize the specified value.
*
* @param value
* The value to normalize.
* @return The normalized value.
*/
public final double normalize(final double value) {
if( value>this.actualHigh ) {
return this.normalizedHigh;
} else if( value<this.actualLow ) {
return this.normalizedLow;
}
else
return ((value - this.actualLow) / (this.actualHigh - this.actualLow))
* (this.normalizedHigh - this.normalizedLow)
+ this.normalizedLow;
}
/**
* Set the action for the field.
*
* @param theAction
* The action for the field.
*/
public final void setAction(final NormalizationAction theAction) {
this.action = theAction;
}
/**
* Set the actual high for the field.
*
* @param theActualHigh
* The actual high for the field.
*/
public final void setActualHigh(final double theActualHigh) {
this.actualHigh = theActualHigh;
}
/**
* Set the actual low for the field.
*
* @param theActualLow
* The theActual low for the field.
*/
public final void setActualLow(final double theActualLow) {
this.actualLow = theActualLow;
}
/**
* Set the name of the field.
*
* @param theName
* The name of the field.
*/
public final void setName(final String theName) {
this.name = theName;
}
/**
* Set the normalized high for the field.
*
* @param theNormalizedHigh
* The normalized high for the field.
*/
public final void setNormalizedHigh(final double theNormalizedHigh) {
this.normalizedHigh = theNormalizedHigh;
}
/**
* Set the normalized low for the field.
*
* @param theNormalizedLow
* The normalized low for the field.
*/
public final void setNormalizedLow(final double theNormalizedLow) {
this.normalizedLow = theNormalizedLow;
}
/** {@inheritDoc} */
@Override
public final String toString() {
final StringBuilder result = new StringBuilder("[");
result.append(getClass().getSimpleName());
result.append(" name=");
result.append(this.name);
result.append(", actualHigh=");
result.append(this.actualHigh);
result.append(", actualLow=");
result.append(this.actualLow);
result.append("]");
return result.toString();
}
}