org.deeplearning4j.nn.params.PretrainParamInitializer Maven / Gradle / Ivy
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* * terms of the Apache License, Version 2.0 which is available at
* * https://www.apache.org/licenses/LICENSE-2.0.
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* * information regarding copyright ownership.
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package org.deeplearning4j.nn.params;
import lombok.val;
import org.deeplearning4j.nn.conf.NeuralNetConfiguration;
import org.nd4j.linalg.api.ndarray.INDArray;
import org.nd4j.linalg.factory.Nd4j;
import org.nd4j.linalg.indexing.NDArrayIndex;
import java.util.Map;
/**
* Pretrain weight initializer.
* Has the visible bias as well as hidden and weight matrix.
*
* @author Adam Gibson
*/
public class PretrainParamInitializer extends DefaultParamInitializer {
private static final PretrainParamInitializer INSTANCE = new PretrainParamInitializer();
public static PretrainParamInitializer getInstance() {
return INSTANCE;
}
public final static String VISIBLE_BIAS_KEY = "v" + DefaultParamInitializer.BIAS_KEY;
@Override
public long numParams(NeuralNetConfiguration conf) {
org.deeplearning4j.nn.conf.layers.BasePretrainNetwork layerConf =
(org.deeplearning4j.nn.conf.layers.BasePretrainNetwork) conf.getLayer();
return super.numParams(conf) + layerConf.getNIn();
}
@Override
public Map init(NeuralNetConfiguration conf, INDArray paramsView, boolean initializeParams) {
Map params = super.init(conf, paramsView, initializeParams);
org.deeplearning4j.nn.conf.layers.BasePretrainNetwork layerConf =
(org.deeplearning4j.nn.conf.layers.BasePretrainNetwork) conf.getLayer();
val nIn = layerConf.getNIn();
val nOut = layerConf.getNOut();
val nWeightParams = nIn * nOut;
INDArray paramsViewReshape = paramsView.reshape(paramsView.length());
INDArray visibleBiasView = paramsViewReshape.get(
NDArrayIndex.interval(nWeightParams + nOut, nWeightParams + nOut + nIn));
params.put(VISIBLE_BIAS_KEY, createVisibleBias(conf, visibleBiasView, initializeParams));
conf.addVariable(VISIBLE_BIAS_KEY);
return params;
}
protected INDArray createVisibleBias(NeuralNetConfiguration conf, INDArray visibleBiasView,
boolean initializeParameters) {
org.deeplearning4j.nn.conf.layers.BasePretrainNetwork layerConf =
(org.deeplearning4j.nn.conf.layers.BasePretrainNetwork) conf.getLayer();
if (initializeParameters) {
INDArray ret = Nd4j.valueArrayOf(new long[]{1, layerConf.getNIn()}, layerConf.getVisibleBiasInit());
visibleBiasView.assign(ret);
}
return visibleBiasView;
}
@Override
public Map getGradientsFromFlattened(NeuralNetConfiguration conf, INDArray gradientView) {
Map out = super.getGradientsFromFlattened(conf, gradientView);
org.deeplearning4j.nn.conf.layers.FeedForwardLayer layerConf =
(org.deeplearning4j.nn.conf.layers.FeedForwardLayer) conf.getLayer();
val nIn = layerConf.getNIn();
val nOut = layerConf.getNOut();
val nWeightParams = nIn * nOut;
INDArray gradientViewReshape = gradientView.reshape(gradientView.length());
INDArray vBiasView = gradientViewReshape.get(
NDArrayIndex.interval(nWeightParams + nOut, nWeightParams + nOut + nIn));
out.put(VISIBLE_BIAS_KEY, vBiasView);
return out;
}
}