org.opensourcephysics.numerics
Interface GeneralStateEvent

All Superinterfaces:

MultiVarFunction, StateEvent

public interface GeneralStateEvent
extends StateEvent

GeneralStateEvent is an extension of the older StateEvents which allows for other types of zero-crossing of the evaluate function, f. An event consists now in that a given numeric value crosses zero (from any direction in croossing events, from positive to negative in the other cases). In crossing and positive events, zeros must be appropriately separated for the solver to find them. Hence, crossing and positive events are NOT appropriated for simultaneous events (an event action triggers another event which was at zero). For this cases use a state event. *

Author:

Francisco Esquembre. November 2007

Field Summary

static int	BISECTION Root finding method using bisection
static int	CROSSING_EVENT
static int	POSITIVE_EVENT
static int	SECANT Root finding method using a line
static int	STATE_EVENT

Method Summary

int	getMaxIterations() Returns the maximum number of iterations allowed when locating the event.
int	getRootFindingMethod() Returns the method used to locate the exact point of the event.
int	getTypeOfEvent() Returns the type of event.

Methods inherited from interface org.opensourcephysics.numerics.StateEvent

action, evaluate, getTolerance

Field Detail

STATE_EVENT

static final int STATE_EVENT

See Also:

Constant Field Values

POSITIVE_EVENT

static final int POSITIVE_EVENT

See Also:

Constant Field Values

CROSSING_EVENT

static final int CROSSING_EVENT

See Also:

Constant Field Values

BISECTION

static final int BISECTION

Root finding method using bisection

See Also:

Constant Field Values

SECANT

static final int SECANT

Root finding method using a line

See Also:

Constant Field Values

Method Detail

getTypeOfEvent

int getTypeOfEvent()

Returns the type of event. One of:

• STATE_EVENT : same as StateEvent, i.e. an event that assumes the state always provides a positive evaluation of f.
• POSITIVE_EVENT : A positive event is a StateEvent in which the event consist in that the function crosses zero from positive to negative.
• CROSSING_EVENT : A crossing event is a StateEvent in which the event consist in that the function crosses zero in ANY direction.

Differently to normal StateEvents, in positive and crossing events, negative values of the function are considered legal states. This implies that zeroes must be appropriately separated (by positive or negative states) for the solver to find them. Hence, positive and crossing events are NOT appropriated for simultaneous events (an event action triggers another event which was at zero).

Returns:

getRootFindingMethod

int getRootFindingMethod()

Returns the method used to locate the exact point of the event. One of:

• BISECTION : Proposes the point at the center of the checked interval
• SECANT : Proposes the point of intersection of a line with the axis

Returns:

getMaxIterations

int getMaxIterations()

Returns the maximum number of iterations allowed when locating the event.

Returns: