The various ODE integrators provide objects implementing this interface to the step handlers. These objects are often custom objects tightly bound to the integrator internal algorithms. The handlers can use these objects to retrieve the state vector at intermediate times between the previous and the current grid points (this feature is often called dense output).
One important thing to note is that the step handlers may be so
tightly bound to the integrators that they often share some internal
state arrays. This imply that one should never use a direct
reference to a step interpolator outside of the step handler, either
for future use or for use in another thread. If such a need arise, the
step interpolator must be copied using the dedicated
copy() method.
org.apache.commons.math3.ode.FirstOrderIntegrator , org.apache.commons.math3.ode.SecondOrderIntegrator , StepHandler
| Modifier and Type | Method and Description |
|---|---|
| public StepInterpolator | |
| public double | |
| public double[] | Returns: derivatives of the state vector at timegetInterpolatedTimeGet the derivatives of the state vector of the interpolated point. |
| public double[] | Returns: interpolated secondary derivatives at the current interpolation dateindex of the secondary set, as returned by index)ExpandableStatefulODE.Get the interpolated secondary derivatives corresponding to the secondary equations. |
| public double[] | Returns: interpolated secondary state at the current interpolation dateindex of the secondary set, as returned by index)ExpandableStatefulODE.Get the interpolated secondary state corresponding to the secondary equations. |
| public double[] | Returns: state vector at timegetInterpolatedTimeGet the state vector of the interpolated point. |
| public double | |
| public double | |
| public boolean | Returns: true if the integration variable (time) increases during integrationCheck if the natural integration direction is forward. |
| public void | setInterpolatedTime(double
time of the interpolated point time)Set the time of the interpolated point. |
| copy | back to summary |
|---|---|
| public StepInterpolator copy() throws MaxCountExceededException Copy the instance. The copied instance is guaranteed to be independent from the original one. Both can be used with different settings for interpolated time without any side effect.
| |
| getCurrentTime | back to summary |
|---|---|
| public double getCurrentTime() Get the current grid point time.
| |
| getInterpolatedDerivatives | back to summary |
|---|---|
| public double[] getInterpolatedDerivatives() throws MaxCountExceededException Get the derivatives of the state vector of the interpolated point. The returned vector is a reference to a reused array, so
it should not be modified and it should be copied if it needs
to be preserved across several calls to the associated
| |
| getInterpolatedSecondaryDerivatives | back to summary |
|---|---|
| public double[] getInterpolatedSecondaryDerivatives(int index) throws MaxCountExceededException Get the interpolated secondary derivatives corresponding to the secondary equations. The returned vector is a reference to a reused array, so it should not be modified and it should be copied if it needs to be preserved across several calls.
| |
| getInterpolatedSecondaryState | back to summary |
|---|---|
| public double[] getInterpolatedSecondaryState(int index) throws MaxCountExceededException Get the interpolated secondary state corresponding to the secondary equations. The returned vector is a reference to a reused array, so
it should not be modified and it should be copied if it needs
to be preserved across several calls to the associated
| |
| getInterpolatedState | back to summary |
|---|---|
| public double[] getInterpolatedState() throws MaxCountExceededException Get the state vector of the interpolated point. The returned vector is a reference to a reused array, so
it should not be modified and it should be copied if it needs
to be preserved across several calls to the associated
| |
| getInterpolatedTime | back to summary |
|---|---|
| public double getInterpolatedTime() Get the time of the interpolated point.
If
| |
| getPreviousTime | back to summary |
|---|---|
| public double getPreviousTime() Get the previous grid point time.
| |
| isForward | back to summary |
|---|---|
| public boolean isForward() Check if the natural integration direction is forward. This method provides the integration direction as specified by the integrator itself, it avoid some nasty problems in degenerated cases like null steps due to cancellation at step initialization, step control or discrete events triggering.
| |
| setInterpolatedTime | back to summary |
|---|---|
| public void setInterpolatedTime(double time) Set the time of the interpolated point. Setting the time outside of the current step is now allowed, but should be used with care since the accuracy of the interpolator will probably be very poor far from this step. This allowance has been added to simplify implementation of search algorithms near the step endpoints. Setting the time changes the instance internal state. This includes
the internal arrays returned in
| |