Continuance

Continuance is a library for handling duration as opposed to absolute time. At present the minimum resolution for measuring duration in Continuance is in hours, with the maximum resolution being a nanosecond.

Current Build Status:

Installation

The continuance gem runs with all Ruby versions >= 1.9.3.

gem 'continuance'

Example

To create a duration of 1 hour is simply.

Continuance::Duration.new(1, 0, 0, 0)

or with a named argument.

Continuance::Duration.new(hours = 1)

To create a duration of 1 hour and 5 minutes is simply.

Continuance::Duration.new(1, 5, 0, 0)

Once again named arguments can be used if preferred. Now to create a more complex duration of 1 hour, 10 minutes, 23.005 seconds.

Continuance::Duration.new(1, 10, 23, 5_000_000)

As we can see the 4th argument of the constructor takes the point second value as a measure nanoseconds. Continuance only supports unsigned whole numbers for each unit. If there is a need to support signed floating point numbers we will look into it.

Math Operations

Duration objects support the math operation + and -. So a duration object can be either be added to another or subtracted from another. The result of each of these operations is another duration object.

For example to add a duration of 1 hour 5 minutes to 6 minutes 32 seconds we can write the following code.

Continuance::Duration.new(1, 0, 5, 0) + Continuance::Duration.new(0, 0, 6, 32)

Collection Operations

Total & average

At present Continuance provides total and average aggregate operations on a collection of duration objects. The Ruby code below demonstrates how to use these collection operations.

duration1 = Continuance::Duration.new(1, 0, 5, 0)
duration2 = Continuance::Duration.new(0, 0, 6, 32)
durations = Continuance::Duration.new([duration1, duration2])
average = durations.average
total = durations.total

The average method returns a Duration object, where as total returns the total number of seconds as a floating point value, this could change in the future. The order of complexity of both operations is O(n). In mathematics average is also referred to as the arithmetic mean and median. The average is aliased as arithmetic mean and median.

Min & Max

The library also supports retrieving the minimum and maximum value for a collection of durations. Like the total and average operations, the order of complexity of the min and max operation is O(n).

Variance & Standard Deviation

The library also supports retrieving the variance and standard deviation for a collection of durations.

Report bugs on GitHub.