MSEWorker.java

/*
 * Copyright [2012-2014] PayPal Software Foundation
 *
 * 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.
 */
package ml.shifu.shifu.core;

import org.encog.ml.data.MLData;
import org.encog.ml.data.MLDataPair;
import org.encog.ml.data.MLDataSet;
import org.encog.ml.data.basic.BasicMLDataPair;
import org.encog.neural.networks.BasicNetwork;
import org.encog.util.concurrency.EngineTask;

/**
 * Mean standard error worker, for parallel compute sub-error then summing
 */
public class MSEWorker implements EngineTask {

    private final BasicNetwork network;
    private final MLDataSet dataSet;
    private final int low;
    private final int high;
    private final MLDataPair pair;

    private double totalError;

    public MSEWorker(BasicNetwork network,
                     MLDataSet dataSet,
                     int low, int high) {
        this.network = network;
        this.dataSet = dataSet;
        this.low = low;
        this.high = high;
        this.pair = BasicMLDataPair.createPair(network.getInputCount(), network.getOutputCount());
        this.totalError = 0.0;
    }

    public void run() {
        for (int i = this.low; i <= this.high; i++) {
            this.dataSet.getRecord(i, pair);
            MLData result = this.network.compute(this.pair.getInput());

            double tmp = result.getData()[0] - this.pair.getIdeal().getData()[0];
            double mse = tmp * tmp;

            this.totalError += mse;
        }
    }

    public double getTotalError() {
        return this.totalError;
    }
}