org.jscience.mathematics.analysis.ode
Class DummyStepInterpolator

java.lang.Object
  org.jscience.mathematics.analysis.ode.AbstractStepInterpolator
      org.jscience.mathematics.analysis.ode.DummyStepInterpolator

All Implemented Interfaces:

java.io.Externalizable, java.io.Serializable, java.lang.Cloneable, StepInterpolator

public class DummyStepInterpolator
extends AbstractStepInterpolator

This class is a step interpolator that does nothing.

This class is used when the "step handler" set up by the user does not need step interpolation. It does not recompute the state when setInterpolatedTime is called. This implies the interpolated state is always the state at the end of the current step.

See Also:

StepHandler, Serialized Form

Field Summary

Fields inherited from class org.jscience.mathematics.analysis.ode.AbstractStepInterpolator

currentState, currentTime, h, interpolatedState, interpolatedTime, previousTime

Constructor Summary

protected	DummyStepInterpolator() Simple constructor.
protected	DummyStepInterpolator(double[] y, boolean forward) Simple constructor.
protected	DummyStepInterpolator(DummyStepInterpolator interpolator) Copy constructor.

Method Summary

java.lang.Object	clone() Copy the instance.
protected void	computeInterpolatedState(double theta, double oneMinusThetaH) Compute the state at the interpolated time.
void	readExternal(java.io.ObjectInput in)
void	writeExternal(java.io.ObjectOutput out)

Methods inherited from class org.jscience.mathematics.analysis.ode.AbstractStepInterpolator

doFinalize, finalizeStep, getCurrentTime, getInterpolatedState, getInterpolatedTime, getPreviousTime, isForward, readBaseExternal, reinitialize, setInterpolatedTime, shift, storeTime, writeBaseExternal

Methods inherited from class java.lang.Object

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

Constructor Detail

DummyStepInterpolator

protected DummyStepInterpolator()

Simple constructor. This constructor builds an instance that is not usable yet, the AbstractStepInterpolator.reinitialize(double[], boolean) method should be called before using the instance in order to initialize the internal arrays. This constructor is used only in order to delay the initialization in some cases. As an example, the RungeKuttaFehlbergIntegrator uses the prototyping design pattern to create the step interpolators by cloning an uninitialized model and latter initializing the copy.

DummyStepInterpolator

protected DummyStepInterpolator(double[] y,
                                boolean forward)

Simple constructor.

Parameters:

y - reference to the integrator array holding the state at the end of the step

forward - integration direction indicator

DummyStepInterpolator

protected DummyStepInterpolator(DummyStepInterpolator interpolator)

Copy constructor.

The copied interpolator should have been finalized before the copy, otherwise the copy will not be able to perform correctly any interpolation and will throw a NullPointerException later. Since we don't want this constructor to throw the exceptions finalization may involve and since we don't want this method to modify the state of the copied interpolator, finalization is not done automatically, it remains under user control.

The copy is a deep copy: its arrays are separated from the original arrays of the instance.

Parameters:

interpolator - interpolator to copy from.

Method Detail

clone

public java.lang.Object clone()

Copy the instance. the copy is a deep copy: its arrays are separated from the original arrays of the instance

Specified by:

clone in class AbstractStepInterpolator

Returns:

a copy of the instance.

computeInterpolatedState

protected void computeInterpolatedState(double theta,
                                        double oneMinusThetaH)
                                 throws DerivativeException

Compute the state at the interpolated time. In this class, this method does nothing: the interpolated state is always the state at the end of the current step.

Specified by:

computeInterpolatedState in class AbstractStepInterpolator

Parameters:

theta - normalized interpolation abscissa within the step (theta is zero at the previous time step and one at the current time step)

oneMinusThetaH - time gap between the interpolated time and the current time

Throws:

DerivativeException - this exception is propagated to the caller if the underlying user function triggers one

writeExternal

public void writeExternal(java.io.ObjectOutput out)
                   throws java.io.IOException

Specified by:

writeExternal in interface java.io.Externalizable

Specified by:

writeExternal in class AbstractStepInterpolator

Throws:

java.io.IOException

readExternal

public void readExternal(java.io.ObjectInput in)
                  throws java.io.IOException

Specified by:

readExternal in interface java.io.Externalizable

Specified by:

readExternal in class AbstractStepInterpolator

Throws:

java.io.IOException