| /* |
| * 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.core.RealFieldElement; |
| import org.apache.commons.math4.legacy.ode.FieldODEStateAndDerivative; |
| |
| /** |
| * This interface represents a handler that should be called after |
| * each successful fixed step. |
| |
| * <p>This interface should be implemented by anyone who is interested |
| * in getting the solution of an ordinary differential equation at |
| * fixed time steps. Objects implementing this interface should be |
| * wrapped within an instance of {@link FieldStepNormalizer} that itself |
| * is used as the general {@link FieldStepHandler} by the integrator. The |
| * {@link FieldStepNormalizer} object is called according to the integrator |
| * internal algorithms and it calls objects implementing this |
| * interface as necessary at fixed time steps.</p> |
| * |
| * @see FieldStepHandler |
| * @see FieldStepNormalizer |
| * @see FieldStepInterpolator |
| * @param <T> the type of the field elements |
| * @since 3.6 |
| */ |
| |
| public interface FieldFixedStepHandler<T extends RealFieldElement<T>> { |
| |
| /** 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 initialState initial time, state vector and derivative |
| * @param finalTime target time for the integration |
| */ |
| void init(FieldODEStateAndDerivative<T> initialState, T finalTime); |
| |
| /** |
| * Handle the last accepted step. |
| * @param state current value of the independent <i>time</i> variable, |
| * state vector and derivative |
| * For efficiency purposes, the {@link FieldStepNormalizer} class reuses |
| * the same array 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 complete array of all |
| * steps), it should build a local copy store this copy. |
| * @param isLast true if the step is the last one |
| */ |
| void handleStep(FieldODEStateAndDerivative<T> state, boolean isLast); |
| |
| } |