/*******************************************************************************
 * 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.api;

import org.deeplearning4j.exception.InvalidStepException;
import org.nd4j.linalg.api.ndarray.INDArray;
import org.deeplearning4j.nn.workspace.LayerWorkspaceMgr;

import java.io.Serializable;

/**
 * Line optimizer interface adapted from mallet
 * @author Adam Gibson
 *
 */
public interface LineOptimizer extends Serializable {
    /**
     * Line optimizer
     * @param parameters the parameters to optimize
     * @param gradient the gradient
     * @param searchDirection  the point/direction to go in
     * @return the last step size used
     * @throws InvalidStepException
     */
    double optimize(INDArray parameters, INDArray gradient, INDArray searchDirection, LayerWorkspaceMgr workspaceMgr) throws InvalidStepException;



}
