temporalCount

Number of events, chart executions, or time since state became active

Syntax

temporalCount(E)

temporalCount(tick)

temporalCount(time_unit)

Description

temporalCount(E) returns the number of occurrences of the event E since the associated state became active.

temporalCount(tick) returns the number of times that the chart has woken up since the associated state became active.

The implicit event tick is not supported when a Stateflow^® chart in a Simulink^® model has input events.

temporalCount(time_unit) returns the length of time that has elapsed since the associated state became active. Specify time_unit as seconds (sec), milliseconds (msec), or microseconds (usec).

Note

Standalone Stateflow charts in MATLAB^® support using temporalCount only as an absolute-time temporal logic operator.

Examples

Perform Action on Event Broadcast

Access successive elements of the array M each time that the chart processes a broadcast of the event E.

In charts in a Simulink model, enter:

on E:
   y = M(temporalCount(E));

Using temporalCount as an event-based temporal logic operator is not supported in standalone charts in MATLAB.

Perform Action on Chart Execution

Store the value of the input data u in successive elements of the array M.

In charts in a Simulink model, enter:

en,du:
   M(temporalCount(tick)+1) = u;

Using temporalCount as an event-based temporal logic operator is not supported in standalone charts in MATLAB.

Determine Time of State Activity

Store the number of milliseconds since the state became active.

en,du:
   y = temporalCount(msec);

Tips

• You can use quotation marks to enclose the keywords 'tick', 'sec', 'msec', and 'usec'. For example, temporalCount('tick') is equivalent to temporalCount(tick).

• The Stateflow chart resets the counter used by the temporalCount operator each time the associated state reactivates.

• The timing for absolute-time temporal logic operators depends on the type of Stateflow chart:

  • Charts in a Simulink model define temporal logic in terms of simulation time.

  • Standalone charts in MATLAB define temporal logic in terms of wall-clock time.

  The difference in timing can affect the behavior of a chart. For example, suppose that this chart is executing the entry action of state A.

  

  • In a Simulink model, the function call to f executes in a single time step and does not contribute to the simulation time. After calling the function f, the chart assigns a value of zero to y.

  • In a standalone chart, the function call to f can take several seconds of wall-clock time to complete. After calling the function f, the chart assigns the nonzero time that has elapsed since state A became active to y.

Version History

Introduced in R2008a