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    
018    package org.apache.commons.math.ode;
019    
020    import org.apache.commons.math.ode.DerivativeException;
021    
022    
023    /** This interface represents a second order integrator for
024     * differential equations.
025     *
026     * <p>The classes which are devoted to solve second order differential
027     * equations should implement this interface. The problems which can
028     * be handled should implement the {@link
029     * SecondOrderDifferentialEquations} interface.</p>
030     *
031     * @see SecondOrderDifferentialEquations
032     * @version $Revision: 1073158 $ $Date: 2011-02-21 22:46:52 +0100 (lun. 21 f??vr. 2011) $
033     * @since 1.2
034     */
035    
036    public interface SecondOrderIntegrator extends ODEIntegrator {
037    
038      /** Integrate the differential equations up to the given time
039       * @param equations differential equations to integrate
040       * @param t0 initial time
041       * @param y0 initial value of the state vector at t0
042       * @param yDot0 initial value of the first derivative of the state
043       * vector at t0
044       * @param t target time for the integration
045       * (can be set to a value smaller thant <code>t0</code> for backward integration)
046       * @param y placeholder where to put the state vector at each
047       * successful step (and hence at the end of integration), can be the
048       * same object as y0
049       * @param yDot placeholder where to put the first derivative of
050       * the state vector at time t, can be the same object as yDot0
051       * @throws IntegratorException if the integrator cannot perform integration
052       * @throws DerivativeException this exception is propagated to the caller if the
053       * underlying user function triggers one
054       */
055      void integrate(SecondOrderDifferentialEquations equations,
056                     double t0, double[] y0, double[] yDot0,
057                     double t, double[] y, double[] yDot)
058          throws DerivativeException, IntegratorException;
059    
060    }