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.fitting.leastsquares; 018 019/** 020 * An algorithm that can be applied to a non-linear least squares problem. 021 * 022 * @since 3.3 023 */ 024public interface LeastSquaresOptimizer { 025 026 /** 027 * Solve the non-linear least squares problem. 028 * 029 * 030 * @param leastSquaresProblem the problem definition, including model function and 031 * convergence criteria. 032 * @return The optimum. 033 */ 034 Optimum optimize(LeastSquaresProblem leastSquaresProblem); 035 036 /** 037 * The optimum found by the optimizer. This object contains the point, its value, and 038 * some metadata. 039 */ 040 //TODO Solution? 041 interface Optimum extends LeastSquaresProblem.Evaluation { 042 043 /** 044 * Get the number of times the model was evaluated in order to produce this 045 * optimum. 046 * 047 * @return the number of model (objective) function evaluations 048 */ 049 int getEvaluations(); 050 051 /** 052 * Get the number of times the algorithm iterated in order to produce this 053 * optimum. In general least squares it is common to have one {@link 054 * #getEvaluations() evaluation} per iterations. 055 * 056 * @return the number of iterations 057 */ 058 int getIterations(); 059 060 } 061 062}