| /* |
| * Licensed to the Apache Software Foundation (ASF) under one or more |
| * contributor license agreements. See the NOTICE file distributed with |
| * this work for additional information regarding copyright ownership. |
| * The ASF licenses this file to You under the Apache License, Version 2.0 |
| * (the "License"); you may not use this file except in compliance with |
| * the License. You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| |
| package org.apache.commons.math4.legacy.ode.sampling; |
| |
| import org.apache.commons.math4.legacy.exception.MaxCountExceededException; |
| |
| |
| /** |
| * This interface represents a handler that should be called after |
| * each successful step. |
| * |
| * <p>The ODE integrators compute the evolution of the state vector at |
| * some grid points that depend on their own internal algorithm. Once |
| * they have found a new grid point (possibly after having computed |
| * several evaluation of the derivative at intermediate points), they |
| * provide it to objects implementing this interface. These objects |
| * typically either ignore the intermediate steps and wait for the |
| * last one, store the points in an ephemeris, or forward them to |
| * specialized processing or output methods.</p> |
| * |
| * @see org.apache.commons.math4.legacy.ode.FirstOrderIntegrator |
| * @see org.apache.commons.math4.legacy.ode.SecondOrderIntegrator |
| * @see StepInterpolator |
| * @since 1.2 |
| */ |
| |
| public interface StepHandler { |
| |
| /** Initialize step handler at the start of an ODE integration. |
| * <p> |
| * This method is called once at the start of the integration. It |
| * may be used by the step handler to initialize some internal data |
| * if needed. |
| * </p> |
| * @param t0 start value of the independent <i>time</i> variable |
| * @param y0 array containing the start value of the state vector |
| * @param t target time for the integration |
| */ |
| void init(double t0, double[] y0, double t); |
| |
| /** |
| * Handle the last accepted step. |
| * @param interpolator interpolator for the last accepted step. For |
| * efficiency purposes, the various integrators reuse the same |
| * object on each call, so if the instance wants to keep it across |
| * all calls (for example to provide at the end of the integration a |
| * continuous model valid throughout the integration range, as the |
| * {@link org.apache.commons.math4.legacy.ode.ContinuousOutputModel |
| * ContinuousOutputModel} class does), it should build a local copy |
| * using the clone method of the interpolator and store this copy. |
| * Keeping only a reference to the interpolator and reusing it will |
| * result in unpredictable behavior (potentially crashing the application). |
| * @param isLast true if the step is the last one |
| * @exception MaxCountExceededException if the interpolator throws one because |
| * the number of functions evaluations is exceeded |
| */ |
| void handleStep(StepInterpolator interpolator, boolean isLast) |
| throws MaxCountExceededException; |
| |
| } |