2019-06-06 15:21:15 +03:00

58 lines
2.1 KiB
Java
Executable File

/*******************************************************************************
* Copyright (c) 2015-2018 Skymind, Inc.
*
* This program and the accompanying materials are made available under the
* terms of the Apache License, Version 2.0 which is available at
* https://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.
*
* SPDX-License-Identifier: Apache-2.0
******************************************************************************/
package org.deeplearning4j.optimize.solvers;
import org.deeplearning4j.nn.api.Model;
import org.deeplearning4j.nn.conf.NeuralNetConfiguration;
import org.deeplearning4j.optimize.api.StepFunction;
import org.deeplearning4j.optimize.api.TrainingListener;
import org.nd4j.linalg.api.ndarray.INDArray;
import org.nd4j.linalg.factory.Nd4j;
import java.util.Collection;
/**
* Stochastic Gradient Descent with Line Search
* @author Adam Gibson
*
*/
public class LineGradientDescent extends BaseOptimizer {
private static final long serialVersionUID = 6336124657542062284L;
public LineGradientDescent(NeuralNetConfiguration conf, StepFunction stepFunction,
Collection<TrainingListener> trainingListeners, Model model) {
super(conf, stepFunction, trainingListeners, model);
}
@Override
public void preProcessLine() {
INDArray gradient = (INDArray) searchState.get(GRADIENT_KEY);
searchState.put(SEARCH_DIR, gradient.dup());
}
@Override
public void postStep(INDArray gradient) {
double norm2 = Nd4j.getBlasWrapper().level1().nrm2(gradient);
if (norm2 > stepMax)
searchState.put(SEARCH_DIR, gradient.dup().muli(stepMax / norm2));
else
searchState.put(SEARCH_DIR, gradient.dup());
searchState.put(GRADIENT_KEY, gradient.dup());
}
}