1 /* 2 * Licensed to the Apache Software Foundation (ASF) under one or more 3 * contributor license agreements. See the NOTICE file distributed with 4 * this work for additional information regarding copyright ownership. 5 * The ASF licenses this file to You under the Apache License, Version 2.0 6 * (the "License"); you may not use this file except in compliance with 7 * the License. You may obtain a copy of the License at 8 * 9 * http://www.apache.org/licenses/LICENSE-2.0 10 * 11 * Unless required by applicable law or agreed to in writing, software 12 * distributed under the License is distributed on an "AS IS" BASIS, 13 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 14 * See the License for the specific language governing permissions and 15 * limitations under the License. 16 */ 17 package org.apache.commons.math4.legacy.fitting; 18 19 import org.apache.commons.math4.legacy.analysis.polynomials.PolynomialFunction; 20 21 /** 22 * Fits points to a {@link 23 * org.apache.commons.math4.legacy.analysis.polynomials.PolynomialFunction.Parametric polynomial} 24 * function. 25 * <br> 26 * The size of the {@link #withStartPoint(double[]) initial guess} array defines the 27 * degree of the polynomial to be fitted. 28 * They must be sorted in increasing order of the polynomial's degree. 29 * The optimal values of the coefficients will be returned in the same order. 30 * 31 * @since 3.3 32 */ 33 public final class PolynomialCurveFitter extends SimpleCurveFitter { 34 /** Parametric function to be fitted. */ 35 private static final PolynomialFunction.Parametric FUNCTION = new PolynomialFunction.Parametric(); 36 37 /** 38 * Constructor used by the factory methods. 39 * 40 * @param initialGuess Initial guess. 41 * @param maxIter Maximum number of iterations of the optimization algorithm. 42 */ 43 private PolynomialCurveFitter(double[] initialGuess, 44 int maxIter) { 45 super(FUNCTION, initialGuess, null, maxIter); 46 } 47 48 /** 49 * Creates a default curve fitter. 50 * Zero will be used as initial guess for the coefficients, and the maximum 51 * number of iterations of the optimization algorithm is set to 52 * {@link Integer#MAX_VALUE}. 53 * 54 * @param degree Degree of the polynomial to be fitted. 55 * @return a curve fitter. 56 * 57 * @see #withStartPoint(double[]) 58 * @see #withMaxIterations(int) 59 */ 60 public static PolynomialCurveFitter create(int degree) { 61 return new PolynomialCurveFitter(new double[degree + 1], Integer.MAX_VALUE); 62 } 63 }