umontreal.iro.lecuyer.simevents

Class ContinuousState

java.lang.Object

umontreal.iro.lecuyer.simevents.ContinuousState

public class ContinuousState
extends java.lang.Object

Represents the portion of the simulator's state associated with continuous-time simulation. Any simulator, including the default static one, can have an associate continuous state which is obtained using the continuousState() method of the Simulator class. This state includes all active integration variables as well as the current integration method.

One of the methods selectEuler, selectRungeKutta2 or selectRungeKutta4 must be called before starting any integration. These methods permit one to select the numerical integration method and the step size h (in time units) that will be used for all continuous-time variables linked to the simulator. For all the methods, an integration step at time t changes the values of the variables from their old values at time t - h to their new values at time t.

Each integration step is scheduled as an event and added to the event list.

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	ContinuousState.IntegMethod

Method Summary

Modifier and Type	Method and Description
java.util.List<Continuous>	getContinuousVariables() Returns the list of continuous-time variables currently integrated by the simulator.
ContinuousState.IntegMethod	integMethod() Return an integer that represent the integration method in use.
void	selectEuler(double h) Selects the Euler method as the integration method, with the integration step size h, in time units.
void	selectRungeKutta2(double h) Selects a Runge-Kutta method of order 2 as the integration method to be used, with step size h.
void	selectRungeKutta4(double h) Selects a Runge-Kutta method of order 4 as the integration method to be used, with step size h.

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Method Detail

getContinuousVariables

public java.util.List<Continuous> getContinuousVariables()

Returns the list of continuous-time variables currently integrated by the simulator. The returned list is updated automatically as variables are added or removed, but it cannot be modified directly. One must instead use startInteg or stopInteg in class Continuous to add or remove variables.

integMethod

public ContinuousState.IntegMethod integMethod()

Return an integer that represent the integration method in use.

Returns:

Interger that represent the integration method in use.

selectEuler

public void selectEuler(double h)

Selects the Euler method as the integration method, with the integration step size h, in time units.

Parameters:

h - integration step, in simulation time units

selectRungeKutta2

public void selectRungeKutta2(double h)

Selects a Runge-Kutta method of order 2 as the integration method to be used, with step size h.

Parameters:

h - integration step, in simulation time units

selectRungeKutta4

public void selectRungeKutta4(double h)

Selects a Runge-Kutta method of order 4 as the integration method to be used, with step size h.

Parameters:

h - integration step, in simulation time units