org.nd4j.linalg.activations.impl.ActivationThresholdedReLU Maven / Gradle / Ivy
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* 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.nd4j.linalg.activations.impl;
import lombok.EqualsAndHashCode;
import lombok.Getter;
import org.nd4j.linalg.activations.BaseActivationFunction;
import org.nd4j.linalg.api.ndarray.INDArray;
import org.nd4j.linalg.api.ops.DynamicCustomOp;
import org.nd4j.linalg.factory.Nd4j;
import org.nd4j.linalg.primitives.Pair;
/**
* Thresholded RELU
*
* f(x) = x for x > theta, f(x) = 0 otherwise. theta defaults to 1.0
*
* @author Max Pumperla
*/
@EqualsAndHashCode
@Getter
public class ActivationThresholdedReLU extends BaseActivationFunction {
public static final double DEFAULT_THETA = 1.0;
private double theta = DEFAULT_THETA;
public ActivationThresholdedReLU() {
this(DEFAULT_THETA);
}
public ActivationThresholdedReLU(double theta) {
this.theta = theta;
}
@Override
public INDArray getActivation(INDArray in, boolean training) {
DynamicCustomOp threshRelu = DynamicCustomOp.builder("thresholdedrelu")
.addOutputs(in).addInputs(in)
.addFloatingPointArguments(theta).build();
Nd4j.getExecutioner().execAndReturn(threshRelu);
return in;
}
@Override
public Pair backprop(INDArray in, INDArray epsilon) {
assertShape(in, epsilon);
DynamicCustomOp threshReluBp = DynamicCustomOp.builder("thresholdedrelu_bp")
.addInputs(in, epsilon).addOutputs(in).addFloatingPointArguments(theta).build();
Nd4j.getExecutioner().execAndReturn(threshReluBp);
return new Pair<>(in, null);
}
@Override
public String toString() {
return "thresholdedrelu(theta=" + theta + ")";
}
}