ROS has the ability to setup a simulated Clock for nodes. TL DR : The Duration API is coming out of its experimental stage and offers a nice DSL to easily work with time durations. a duration instance with sec = -1, nsec = 5e8 represents a duration of -0.5 seconds and not -1.5 seconds. Beware that negative durations interpret sec and nsec so that float_time = sec + nsec * 10e-9, so e.g. Spending time There are other ways we can break time down more quickly and efficiently, in order to work out durations. Enter the number of hours and/or minutes you wish to add to or subtract from the clock time. If the time() - starttime is 3 seconds, this prints Runtime: 3 seconds. The duration of time that has passed is 20 minutes. From a selected clock time, add or subtract hours and/or minutes Enter clock time information at 'From:' Enter hours and minutes. It assumes that the final duration of the tasks can include weekends and holidays. In that case, the MFT should calculate the output time stamp from. In the first example in the Synopsis, using duration(intervalseconds). By default, dhtmlxGantt calculates the duration of tasks in calendar time. The output time stamps or durations might not match the input because the MFT is holding back data or breaking the output into different-sized pieces than the input. Time cannot be negative, while durations can hold both positive and negative values (represented by negative sec nsec is always non-negative). The time stamps and durations of the input samples should be preserved on the output samples as much as possible. Time Calculator: Duration Between Two Times and Dates. Times and durations have identical representations: int32 sec Durations Creating Clone Humanize Milliseconds Seconds Minutes Hours Days Weeks Months Years Add Time Subtract Time Using Duration with Diff As Unit of Time. Each Duration is composed of a whole number of seconds and a fractional. "today at 5pm") whereas a Duration is a period of time (e.g. A Duration type to represent a span of time, typically used for system timeouts. How many years, months, days, hours, minutes, and seconds are there between two moments in time Count Days Add Days Workdays Add Workdays Weekday Week.
ROS has builtin time and duration primitive types, which roslib provides as the ros::Time and ros::Duration classes, respectively. Time Calculator: Duration Between Two Times and Dates. timeSinceEpoch.See also: ros::TimeBase API docs, ros::DurationBase API docs Date and time expressions use Date or Duration values to produce a DateTime, Date, Time, Duration, or Number value.