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.analysis.interpolation;
018
019import org.apache.commons.math4.legacy.analysis.polynomials.PolynomialFunctionLagrangeForm;
020import org.apache.commons.math4.legacy.exception.DimensionMismatchException;
021import org.apache.commons.math4.legacy.exception.NonMonotonicSequenceException;
022import org.apache.commons.math4.legacy.exception.NumberIsTooSmallException;
023
024/**
025 * Implements the <a href="http://mathworld.wolfram.com/NevillesAlgorithm.html">
026 * Neville's Algorithm</a> for interpolation of real univariate functions. For
027 * reference, see <b>Introduction to Numerical Analysis</b>, ISBN 038795452X,
028 * chapter 2.
029 * <p>
030 * The actual code of Neville's algorithm is in PolynomialFunctionLagrangeForm,
031 * this class provides an easy-to-use interface to it.</p>
032 *
033 * @since 1.2
034 */
035public class NevilleInterpolator implements UnivariateInterpolator {
036    /**
037     * Computes an interpolating function for the data set.
038     *
039     * @param x Interpolating points.
040     * @param y Interpolating values.
041     * @return a function which interpolates the data set
042     * @throws DimensionMismatchException if the array lengths are different.
043     * @throws NumberIsTooSmallException if the number of points is less than 2.
044     * @throws NonMonotonicSequenceException if two abscissae have the same
045     * value.
046     */
047    @Override
048    public PolynomialFunctionLagrangeForm interpolate(double[] x, double[] y)
049        throws DimensionMismatchException,
050               NumberIsTooSmallException,
051               NonMonotonicSequenceException {
052        return new PolynomialFunctionLagrangeForm(x, y);
053    }
054}