Working with Recorded Timings

Overview

The basic examples covered how to start and stop timers and how to use lap times. However, the methods introduced only allow for printing the current state. With Timekeeper, you can also access the underlying timings for each lap, providing you with the raw measurements and some convenience properties.

If you not only want to print the timings but also access them, e.g. in order to do calculations, Timekeeper got your back. You can use stop(_:) or lap(_:), both of which return the timing in its current state.

// Start a new timing
Timekeeper.shared.start("measurement")


for _ in 0..<100 {
    operationToMeasure()


    // Records a lap without printing
    Timekeeper.shared.lap("measurement")
}


// Stops the timing and returns it without printing
let timing = Timekeeper.shared.stop("measurement")

The code above shows you how to retrieve the timing from Timekeeper after stopping the timer. You could retrieve intermediate timings from the lap(_:) function as well.

Accessing Timing Data

The timing struct provides you with the start and end times, as well as with all intermediate laps.

If the timer was stopped and the end time was set, the totalDuration property returns the difference between end and start time in seconds.

The lapTimes property on the timing returns a list of all time deltas between the individual measurement points.

The possible number of time deltas in the list relates to the recorded times as follows:

• 0, if only the start time and no internediate laps nor the end time is set.

• n, if the start time and n intermediate laps are set.

• n+1 if the start time, n intermediate laps and the end time is set.

This implies that a stopped timing with no intermediate laps contains exactly 1 lap time delta.

There are also some mathematical functions pre-defined on the lap times. These include lapTimeMedian for the median lap time, lapTimeAverage for the arithmetic mean of the lap times, lapTimeStandardDeviation for the standard deviation 𝜎 as well as lapTimeVariance for the variance 𝜎² of the set of lap times.