elapsed, et

Time since state became active

Syntax

elapsed(sec)

et

Description

elapsed(sec) returns the length of time that has elapsed since the associated state became active.

et is an alternative way to execute elapsed(sec).

Note

The expressions elapsed(sec) and et are equivalent to temporalCount(sec).

Examples

Determine Time of State Activity

Store the number of seconds since the state became active.

en,du:
   y = elapsed(sec);

Display Elapsed Time

When the chart processes a broadcast of the event E, transition out of the associated state and display the elapsed time since the state became active.

E{disp(et);}

Tips

• In state and transition actions, you can use quotation marks to enclose the keyword 'sec'. For example, elapsed('sec') is equivalent to elapsed(sec).

• The Stateflow^® chart resets the counter used by the elapsed 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 R2017a