/*
 *  ******************************************************************************
 *  *
 *  *
 *  * 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.
 *  *
 *  *  See the NOTICE file distributed with this work for additional
 *  *  information regarding copyright ownership.
 *  * 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.
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 *  * SPDX-License-Identifier: Apache-2.0
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 */

package org.deeplearning4j.optimize.stepfunctions;

import org.deeplearning4j.optimize.api.StepFunction;
import org.nd4j.linalg.api.ndarray.INDArray;
import org.nd4j.linalg.factory.Nd4j;

public class NegativeDefaultStepFunction implements StepFunction {

    @Override
    public void step(INDArray parameters, INDArray searchDirection, double step) {
        Nd4j.getBlasWrapper().level1().axpy(searchDirection.length(), -step, searchDirection, parameters);
    }

    @Override
    public void step(INDArray x, INDArray line) {
        step(x, line, 1.0);
    }

    @Override
    public void step() {
        throw new UnsupportedOperationException();
    }
}
