Package org.apache.commons.math3.ode

Class JacobianMatrices.MainStateJacobianWrapper

java.lang.Object

org.apache.commons.math3.ode.JacobianMatrices.MainStateJacobianWrapper

All Implemented Interfaces:

FirstOrderDifferentialEquations, MainStateJacobianProvider

Enclosing class:

JacobianMatrices

private static class JacobianMatrices.MainStateJacobianWrapper
extends Object
implements MainStateJacobianProvider

Wrapper class to compute jacobian matrices by finite differences for ODE which do not compute them by themselves.

Field Summary

Fields

Modifier and Type	Field	Description
private final double[]	hY	Steps for finite difference computation of the jacobian df/dy w.r.t.
private final FirstOrderDifferentialEquations	ode	Raw ODE without jacobians computation skill to be wrapped into a MainStateJacobianProvider.

Constructor Summary

Constructors

Constructor	Description
MainStateJacobianWrapper(FirstOrderDifferentialEquations ode, double[] hY)	Wrap a FirstOrderDifferentialEquations into a MainStateJacobianProvider.

Method Summary

Modifier and Type	Method	Description
void	computeDerivatives(double t, double[] y, double[] yDot)	Get the current time derivative of the state vector.
void	computeMainStateJacobian(double t, double[] y, double[] yDot, double[][] dFdY)	Compute the jacobian matrix of ODE with respect to main state.
int	getDimension()	Get the dimension of the problem.

Methods inherited from class java.lang.Object

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

Field Details

ode

private final FirstOrderDifferentialEquations ode

Raw ODE without jacobians computation skill to be wrapped into a MainStateJacobianProvider.

hY

private final double[] hY

Steps for finite difference computation of the jacobian df/dy w.r.t. state.

Constructor Details

MainStateJacobianWrapper

MainStateJacobianWrapper(FirstOrderDifferentialEquations ode,
 double[] hY)
                  throws DimensionMismatchException

Wrap a FirstOrderDifferentialEquations into a MainStateJacobianProvider.

Parameters:

ode - original ODE problem, without jacobians computation skill

hY - step sizes to compute the jacobian df/dy

Throws:

DimensionMismatchException - if there is a dimension mismatch between the steps array hY and the equation dimension

Method Details

getDimension

public int getDimension()

Get the dimension of the problem.

Specified by:

getDimension in interface FirstOrderDifferentialEquations

Returns:

dimension of the problem

computeDerivatives

public void computeDerivatives(double t,
 double[] y,
 double[] yDot)
                        throws MaxCountExceededException,
DimensionMismatchException

Get the current time derivative of the state vector.

Specified by:

computeDerivatives in interface FirstOrderDifferentialEquations

Parameters:

t - current value of the independent time variable

y - array containing the current value of the state vector

yDot - placeholder array where to put the time derivative of the state vector

Throws:

MaxCountExceededException - if the number of functions evaluations is exceeded

DimensionMismatchException - if arrays dimensions do not match equations settings

computeMainStateJacobian

public void computeMainStateJacobian(double t,
 double[] y,
 double[] yDot,
 double[][] dFdY)
                              throws MaxCountExceededException,
DimensionMismatchException

Compute the jacobian matrix of ODE with respect to main state.

Specified by:

computeMainStateJacobian in interface MainStateJacobianProvider

Parameters:

t - current value of the independent time variable

y - array containing the current value of the main state vector

yDot - array containing the current value of the time derivative of the main state vector

dFdY - placeholder array where to put the jacobian matrix of the ODE w.r.t. the main state vector

Throws:

MaxCountExceededException - if the number of functions evaluations is exceeded

DimensionMismatchException - if arrays dimensions do not match equations settings