HasNumericState (Artisynth API documentation)

All Known Subinterfaces:

CollidableDynamicComponent, DynamicAgent, DynamicComponent, MaterialStateObject, MotionTargetComponent

All Known Implementing Classes:

AxialSpring, BackNode3d, BeamBody, BodyConnector, BSpline3dElement, CollisionHandler, CollisionManager, ConstrainerBase, CustomJoint, CylindricalJoint, DeformableBody, DicomPlaneViewer, DicomViewer, DynamicComponentBase, EBBeamBody, EllipsoidJoint, EllipsoidJoint3d, FemCutPlane, FemElement, FemElement3d, FemElement3dBase, FemMarker, FemModel3d, FemModelDeformer, FemModelFrame, FemMuscleModel, FemNode, FemNode3d, FixedAxisJoint, Frame, FrameExciter, FrameFem3dConstraint, FrameMarker, FrameNode3d, FrameSpring, FreeJoint, GenericMarker, GimbalJoint, HexElement, HingeJoint, HydrostatModel, ImageViewer, JointBase, JointBasedMovingMarker, JointConditionalMarker, JointCoordinateCoupling, LinearPointConstraint, Marker, MaxwellAxialMaterial, MechSystemBase.ConstraintForceStateSaver, MFreeElement3d, MFreeModel3d, MFreeMuscleModel, MFreeNode3d, Millard2012AxialMuscle, MultiPointMuscle, MultiPointMuscleVia, MultiPointSpring, MultiPointSpring.WrapSegment, Muscle, MuscleBundle, MuscleExciter, NiftiViewer, OpenSimCustomJoint, Particle, ParticleConstraintBase, ParticleLineConstraint, ParticleMeshConstraint, ParticlePlaneConstraint, PlanarConnector, PlanarJoint, PlanarPoint, PlanarTranslationJoint, Point, PointSpringBase, PointToPointMuscle, PyramidElement, QLVState, QuadhexElement, QuadpyramidElement, QuadtetElement, QuadwedgeElement, RenderableConstrainerBase, RevoluteJoint, RigidBody, RigidCompositeBody, RigidCylinder, RigidEllipsoid, RigidMesh, RigidSphere, RigidTorus, RollPitchJoint, SegmentedPlanarConnector, ShellElement3d, ShellQuadElement, ShellTriElement, SimpleCoordinateCoupler, SkewedUniversalJoint, SkinMarker, SliderJoint, SlottedHingeJoint, SolidJoint, SphericalJoint, SphericalJointBase, SphericalRpyJoint, SpongeModel, TargetFrame, TargetPoint, TetElement, TexturePlaneBase, Thelen2003AxialMuscle, UniversalJoint, ViscoelasticState, WedgeElement
```
public interface HasNumericState
```
Indicates a model component that has state information that can be stored inside a DataBuffer.

Method Summary

All Methods Instance Methods Abstract Methods Default Methods
Modifier and Type	Method and Description
`default void`	`advanceState(double t0, double t1)` If `requiresAdvance()` and `hasState()` both return `true`, then this method is called each time step by the system integrator to update this component's state.
`default int`	`getAuxVarDerivative(double[] buf, int idx)` If this component has auxiliary variables, returns the current values of their derivatives in `buf`, starting at the location `idx`.
`default int`	`getAuxVarState(double[] buf, int idx)` If this component has auxiliary variables, returns their values in `buf`, starting at the location `idx`.
`void`	`getState(DataBuffer data)` Saves state information for this component by adding data to the supplied DataBuffer.
`default int`	`getStateVersion()` Returns a version number for this component's state.
`boolean`	`hasState()` Returns `true` if this component currently holds state.
`default int`	`numAuxVars()` Returns the number of auxiliary variables associated with this component, or 0 if there are no auxiliary variables.
`default boolean`	`requiresAdvance()` Returns `true` if the state of this component must be updated each time step using `advanceState(double, double)`.
`default int`	`setAuxVarState(double[] buf, int idx)` If this component has auxiliary variables, sets them from the values in `buf`, starting at the location `idx`.
`void`	`setState(DataBuffer data)` Restores the state for this component by reading from the supplied data buffer, starting at the current buffer offsets.

- Method Detail
  - hasState
```
boolean hasState()
```
    Returns true if this component currently holds state. This allows the presence of state to depend on the component's configuration.
    
    Returns:
    
    true if this component holds state
  - getState
```
void getState(DataBuffer data)
```
    Saves state information for this component by adding data to the supplied DataBuffer. Existing data in the buffer should not be disturbed.
    
    Parameters:
    
    data - buffer for storing the state values.
  - setState
```
void setState(DataBuffer data)
```
    Restores the state for this component by reading from the supplied data buffer, starting at the current buffer offsets.
    
    Parameters:
    
    data - buffer containing the state information
  - getStateVersion
```
default int getStateVersion()
```
    Returns a version number for this component's state. When the version number changes, any previously saved state should be considered no longer compatible. The default implementation of this method always returns 0, indicating that state compatibility never changes.
  - requiresAdvance
```
default boolean requiresAdvance()
```
    Returns true if the state of this component must be updated each time step using advanceState(double, double).
    
    Returns:
    
    true if advanceState must be called
  - advanceState
```
default void advanceState(double t0,
                          double t1)
```
    If requiresAdvance() and hasState() both return true, then this method is called each time step by the system integrator to update this component's state. For single step integrators, the method is called once at the start of the integration, with t0 and t1 set to the step's start and end times. For multi-step integrators (such as Runge Kutta), the method is called for each sub-step, with t0 and t1 set to the sub-step's time bounds. Multi-step integrators will also use getState(maspack.util.DataBuffer) and setState(maspack.util.DataBuffer) to save and restore state as required.
    
    Parameters:
    
    t0 - beginning time associated with the time step or sub-step
    
    t1 - end time associated with the time step or sub-step
  - numAuxVars
```
default int numAuxVars()
```
    Returns the number of auxiliary variables associated with this component, or 0 if there are no auxiliary variables.
    If hasState() returns true and the component has auxiliary variables, the variables are updated each time step by the system integrator using explcit integration of the form
```
 w += h dwdt
 
```
    where h is a time increment, w is a vector of variables accessed using getAuxVarState(double[], int) and setAuxVarState(double[], int), and dwdt is a time derivative obtained using getAuxVarDerivative(double[], int). For single step integrators, this will be done once at the start of the integration, with h set to the time step size. For multi-step integrators (such as Runge Kutta), this will be done at the start of each sub-step, with h set to the sub-step size.
    If present, auxiliary variables are also assumed to be contained within the state accessed using getState(maspack.util.DataBuffer) and setState(maspack.util.DataBuffer).
    Returns:
    
    number of auxiliary variables.
  - getAuxVarState
```
default int getAuxVarState(double[] buf,
                           int idx)
```
    If this component has auxiliary variables, returns their values in buf, starting at the location idx. See numAuxVars() for a description of auxiliary variables. The method returns idx + num, where num is the number of variables.
    
    Parameters:
    
    buf - returns the variable values
    
    idx - starting point within buf
    
    Returns:
    
    idx plus the number of variables
  - setAuxVarState
```
default int setAuxVarState(double[] buf,
                           int idx)
```
    If this component has auxiliary variables, sets them from the values in buf, starting at the location idx. See numAuxVars() for a description of auxiliary variables. The method returns idx + num, where num is the number of variables.
    
    Parameters:
    
    buf - contains the new variable values
    
    idx - starting point within buf
    
    Returns:
    
    idx plus the number of variables
  - getAuxVarDerivative
```
default int getAuxVarDerivative(double[] buf,
                                int idx)
```
    If this component has auxiliary variables, returns the current values of their derivatives in buf, starting at the location idx. See numAuxVars() for a description of auxiliary variables. The method returns idx + num, where num is the number of variables.
    
    Parameters:
    
    buf - returns the variable derivative values
    
    idx - starting point within buf
    
    Returns:
    
    idx plus the number of variables

Interface HasNumericState

Method Summary

Method Detail

hasState

getState

setState

getStateVersion

requiresAdvance

advanceState

numAuxVars

getAuxVarState

setAuxVarState

getAuxVarDerivative