/*
* Encog(tm) Core v2.5 - Java Version
* http://www.heatonresearch.com/encog/
* http://code.google.com/p/encog-java/
* Copyright 2008-2010 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.engine.network.train.prop;
import org.encog.engine.data.EngineDataSet;
import org.encog.engine.network.flat.FlatNetwork;
/**
* Train the flat network using Manhattan update rule.
*/
public class TrainFlatNetworkManhattan extends TrainFlatNetworkProp {
/**
* The zero tolerance to use.
*/
private final double zeroTolerance;
/**
* The learning rate.
*/
private double learningRate;
/**
* Construct a trainer for flat networks to use the Manhattan update rule.
*
* @param network
* The network to train.
* @param training
* The training data to use.
* @param learningRate
* The learning rate to use.
*/
public TrainFlatNetworkManhattan(final FlatNetwork network,
final EngineDataSet training, final double learningRate) {
super(network, training);
this.learningRate = learningRate;
this.zeroTolerance = RPROPConst.DEFAULT_ZERO_TOLERANCE;
}
/**
* Calculate the amount to change the weight by.
*
* @param gradients
* The gradients.
* @param lastGradient
* The last gradients.
* @param index
* The index to update.
* @return The amount to change the weight by.
*/
@Override
public double updateWeight(final double[] gradients,
final double[] lastGradient, final int index) {
if (Math.abs(gradients[index]) < this.zeroTolerance) {
return 0;
} else if (gradients[index] > 0) {
return this.learningRate;
} else {
return -this.learningRate;
}
}
/**
* @return the learningRate
*/
public double getLearningRate() {
return learningRate;
}
/**
* @param learningRate the learningRate to set
*/
public void setLearningRate(double learningRate) {
this.learningRate = learningRate;
}
}