package org.spaceroots.mantissa.ode;

/** This interface represents a second order integrator for
 * differential equations.

 * 
The classes which are devoted to solve second order differential
 * equations should implement this interface. The problems which can
 * be handled should implement the {@link
 * SecondOrderDifferentialEquations} interface.

 * @see SecondOrderDifferentialEquations

 * @version $Id: SecondOrderIntegrator.java 1599 2004-08-22 12:43:12Z luc $
 * @author L. Maisonobe

 */

public interface SecondOrderIntegrator {

  /** Get the name of the method.
   * @return name of the method
   */
  public String getName();

  /** Set the step handler for this integrator.
   * The handler will be called by the integrator for each accepted
   * step.
   * @param handler handler for the accepted steps
   */
  public void setStepHandler (StepHandler handler);

  /** Get the step handler for this integrator.
   * @return the step handler for this integrator
   */
  public StepHandler getStepHandler();

  /** Integrate the differential equations up to the given time
   * @param equations differential equations to integrate
   * @param t0 initial time
   * @param y0 initial value of the state vector at t0
   * @param yDot0 initial value of the first derivative of the state
   * vector at t0
   * @param t target time for the integration
   * (can be set to a value smaller thant t0 for backward integration)
   * @param y placeholder where to put the state vector at each
   * successful step (and hence at the end of integration), can be the
   * same object as y0
   * @param yDot placeholder where to put the first derivative of
   * the state vector at time t, can be the same object as yDot0
   * @throws IntegratorException if the integrator cannot perform integration
   * @throws DerivativeException this exception is propagated to the caller if the
   * underlying user function triggers one
   */
  public void integrate(SecondOrderDifferentialEquations equations,
                        double t0, double[] y0, double[] yDot0,
                        double t, double[] y, double[] yDot)
  throws DerivativeException, IntegratorException;

}