duration-helper {clock}

Construct a duration

Description

These helpers construct durations of the specified precision. Durations represent units of time.

Durations are separated into two categories:

Calendrical

• year

• quarter

• month

Chronological

• week

• day

• hour

• minute

• second

• millisecond

• microsecond

• nanosecond

Calendrical durations are generally used when manipulating calendar types, like year-month-day. Chronological durations are generally used when working with time points, like sys-time or naive-time.

Usage

duration_years(n = integer())

duration_quarters(n = integer())

duration_months(n = integer())

duration_weeks(n = integer())

duration_days(n = integer())

duration_hours(n = integer())

duration_minutes(n = integer())

duration_seconds(n = integer())

duration_milliseconds(n = integer())

duration_microseconds(n = integer())

duration_nanoseconds(n = integer())

Arguments

n

⁠[integer]⁠

The number of units of time to use when creating the duration.

Value

A duration of the specified precision.

Internal Representation

Durations are internally represented as an integer number of "ticks" along with a ratio describing how it converts to a number of seconds. The following duration ratios are used in clock:

• ⁠1 year == 31556952 seconds⁠

• ⁠1 quarter == 7889238 seconds⁠

• ⁠1 month == 2629746 seconds⁠

• ⁠1 week == 604800 seconds⁠

• ⁠1 day == 86400 seconds⁠

• ⁠1 hour == 3600 seconds⁠

• ⁠1 minute == 60 seconds⁠

• ⁠1 second == 1 second⁠

• ⁠1 millisecond == 1 / 1000 seconds⁠

• ⁠1 microsecond == 1 / 1000000 seconds⁠

• ⁠1 nanosecond == 1 / 1000000000 seconds⁠

A duration of 1 year is defined to correspond to the average length of a proleptic Gregorian year, i.e. 365.2425 days.

A duration of 1 month is defined as exactly 1/12 of a year.

A duration of 1 quarter is defined as exactly 1/4 of a year.

A duration of 1 week is defined as exactly 7 days.

These conversions come into play when doing operations like adding or flooring durations. Generally, you add two calendrical durations together to get a new calendrical duration, rather than adding a calendrical and a chronological duration together. The one exception is duration_cast(), which can cast durations to any other precision, with a potential loss of information.

Examples

duration_years(1:5)
duration_nanoseconds(1:5)