duration

Time during which condition is valid

Syntax

time = duration(condition)

time = duration(condition,time_unit)

Description

time = duration(condition) returns the length of time, in seconds, that condition stays true and the associated state became active.

time = duration(condition,time_unit) returns the length of time in the unit specified by time_unit.

Note

The temporal logic operator duration is not supported in standalone charts in MATLAB^®.

Examples

Guard Transition with Temporal Condition

Transition out of the state when the variable x has been greater than or equal to 0 for longer than 0.1 seconds.

[duration(x>=0) > 0.1]

Determine Elapsed Time

Store the number of milliseconds since the variable x became greater than 5 and the state became active.

en,du:
   y = duration(x>5,msec);

Input Arguments

condition — Logical condition

true | false

Logical condition, specified as true or false. You can specify the value of condition by using an expression that evaluates to true or false. The operator evaluates condition at each time step.

condition does not support expressions that depend on local or output data.

Example: duration(u)

Example: duration(u>=0)

time_unit — Units of time

sec (default) | msec | usec

Units of time that duration returns, specified in seconds (sec), milliseconds (msec), or microseconds (usec).

Tips

• You can use quotation marks to enclose the keywords 'sec', 'msec', and 'usec'. For example, duration(x > 0,'sec') is equivalent to duration(x > 0,sec).

• The Stateflow^® chart resets the value of the duration operator if the conditional expression C becomes false or if the associated state becomes inactive.

• The duration operator does not support conditions that depend on local or output structures. For more information, see Access Bus Signals Through Stateflow Structures.

Version History

Introduced in R2017a