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 */ 017 018package org.apache.commons.math4.legacy.ode.nonstiff; 019 020import org.apache.commons.math4.legacy.core.RealFieldElement; 021 022/** This interface represents an integrator based on Butcher arrays. 023 * @see RungeKuttaFieldIntegrator 024 * @see EmbeddedRungeKuttaFieldIntegrator 025 * @param <T> the type of the field elements 026 * @since 3.6 027 */ 028 029public interface FieldButcherArrayProvider<T extends RealFieldElement<T>> { 030 031 /** Get the time steps from Butcher array (without the first zero). 032 * @return time steps from Butcher array (without the first zero 033 */ 034 T[] getC(); 035 036 /** Get the internal weights from Butcher array (without the first empty row). 037 * @return internal weights from Butcher array (without the first empty row) 038 */ 039 T[][] getA(); 040 041 /** Get the external weights for the high order method from Butcher array. 042 * @return external weights for the high order method from Butcher array 043 */ 044 T[] getB(); 045}