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
18 package org.apache.commons.math4.legacy.ode.nonstiff;
19
20 import org.apache.commons.math4.legacy.core.RealFieldElement;
21
22 /** This interface represents an integrator based on Butcher arrays.
23 * @see RungeKuttaFieldIntegrator
24 * @see EmbeddedRungeKuttaFieldIntegrator
25 * @param <T> the type of the field elements
26 * @since 3.6
27 */
28
29 public interface FieldButcherArrayProvider<T extends RealFieldElement<T>> {
30
31 /** Get the time steps from Butcher array (without the first zero).
32 * @return time steps from Butcher array (without the first zero
33 */
34 T[] getC();
35
36 /** Get the internal weights from Butcher array (without the first empty row).
37 * @return internal weights from Butcher array (without the first empty row)
38 */
39 T[][] getA();
40
41 /** Get the external weights for the high order method from Butcher array.
42 * @return external weights for the high order method from Butcher array
43 */
44 T[] getB();
45 }