dm3 / timesdates.jl

Nanosecond resolution for Time and Date, TimeZones

TimesDates

Nanosecond Resolvable Times with Dates, or Times with Dates in TimeZones.

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Copyright © 2018 by Jeffrey Sarnoff.    This work is made available under The MIT License.

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Setup

install

This package expects Julia v1 (v0.7 is allowed)

pkg> up
pkg> add TimeZones
pkg> add CompoundPeriods
pkg> add TimesDates
pkg> precompile

use

using TimesDates, CompoundPeriods, TimeZones, Dates

The Design

This package provides TimeDate to hold the date and time of day given in nanoseconds (or more coarsely). And providesTimeDateZone to holds the the date and time of day in nanoseconds with a timezone. This work relies heavily on Dates and TimeZones; most of the attention to detail plays through.

Dates has a Time type that has nanosecond resolution; it is not well supported, even within Dates. This Time type recognizes strings only if they are limited to millisecond resolution. Only millisecond resolved times are relevant to DateTimes. While at present limited by this millisecond barrier, TimeZones is a laudable package with active support. I expect an eventual melding of what's best.

Here, the inner dynamics rely upon the Period types (Year .. Day, Hour, .., Nanosecond) and CompoundPeriod all provided by Dates. We distinguish slowtime, which is millisecond resolved, from a nanosecond resolved fasttime.

The general approach is separate the date, slowtime, fasttime, and timezone (if appropriate), then use the date, slowtime and timezone (if appropriate) to obtain a coarse result using the facilities provided by the Date and TimeZones packages. We refine the coarse result by adding or subtracting the fasttime, as appropriate.

Acknowledgements

This work is built atop Dates and TimeZones.

While both are collaborative works, a few people deserve mention:

• Dates: Jacob Quinn and Stefan Karpinski
• TimeZones: Curtis Vogt
• early work on timezones: Avik Sengupta