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.integration;
018
019import org.apache.commons.math4.legacy.analysis.UnivariateFunction;
020
021/**
022 * Interface for univariate real integration algorithms.
023 *
024 * @since 1.2
025 */
026public interface UnivariateIntegrator {
027
028    /**
029     * Get the relative accuracy.
030     *
031     * @return the accuracy
032     */
033    double getRelativeAccuracy();
034
035    /**
036     * Get the absolute accuracy.
037     *
038     * @return the accuracy
039     */
040    double getAbsoluteAccuracy();
041
042    /**
043     * Get the min limit for the number of iterations.
044     *
045     * @return the actual min limit
046     */
047    int getMinimalIterationCount();
048
049    /**
050     * Get the upper limit for the number of iterations.
051     *
052     * @return the actual upper limit
053     */
054    int getMaximalIterationCount();
055
056    /**
057     * Integrate the function in the given interval.
058     *
059     * @param maxEval Maximum number of evaluations.
060     * @param f the integrand function
061     * @param min the lower bound for the interval
062     * @param max the upper bound for the interval
063     * @return the value of integral
064     * @throws org.apache.commons.math4.legacy.exception.TooManyEvaluationsException if the maximum number of function
065     * evaluations is exceeded
066     * @throws org.apache.commons.math4.legacy.exception.MaxCountExceededException if the maximum iteration count is exceeded
067     * or the integrator detects convergence problems otherwise
068     * @throws org.apache.commons.math4.legacy.exception.MathIllegalArgumentException if {@code min > max} or the endpoints do not
069     * satisfy the requirements specified by the integrator
070     * @throws org.apache.commons.math4.legacy.exception.NullArgumentException if {@code f} is {@code null}.
071     */
072    double integrate(int maxEval, UnivariateFunction f, double min, double max);
073
074    /**
075     * Get the number of function evaluations of the last run of the integrator.
076     *
077     * @return number of function evaluations
078     */
079    int getEvaluations();
080
081    /**
082     * Get the number of iterations of the last run of the integrator.
083     *
084     * @return number of iterations
085     */
086    int getIterations();
087}