001/*
002 * Licensed to the Apache Software Foundation (ASF) under one or more
003 * contributor license agreements.  See the NOTICE file distributed with
004 * this work for additional information regarding copyright ownership.
005 * The ASF licenses this file to You under the Apache License, Version 2.0
006 * (the "License"); you may not use this file except in compliance with
007 * the License.  You may obtain a copy of the License at
008 *
009 *      http://www.apache.org/licenses/LICENSE-2.0
010 *
011 * Unless required by applicable law or agreed to in writing, software
012 * distributed under the License is distributed on an "AS IS" BASIS,
013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
014 * See the License for the specific language governing permissions and
015 * limitations under the License.
016 */
017package org.apache.commons.math4.legacy.fitting.leastsquares;
018
019import org.apache.commons.math4.legacy.linear.RealMatrix;
020import org.apache.commons.math4.legacy.linear.RealVector;
021
022/**
023 * A interface for functions that compute a vector of values and can compute their
024 * derivatives (Jacobian).
025 *
026 * @since 3.4
027 */
028public interface ValueAndJacobianFunction extends MultivariateJacobianFunction {
029    /**
030     * Compute the value.
031     *
032     * @param params Point.
033     * @return the value at the given point.
034     */
035    RealVector computeValue(double[] params);
036
037    /**
038     * Compute the Jacobian.
039     *
040     * @param params Point.
041     * @return the Jacobian at the given point.
042     */
043    RealMatrix computeJacobian(double[] params);
044}