Date Stamp

Potentially redundant pages (merge?): DateStamp, SigningWithaDate, ConsiderTimestampingYourWriting

Writing date stamps in this form: yyyymmdd is recognized in the LinkPattern on some wikis. It's valid for dates in all but the first and its previous millennia, and valid until y10k. If we consider a datestamp of ymmdd where any number of digits are valid for the year, it resolves even those problems. Therefore, JuliusCaesar was assassinated on -430315 ... beware the IdesOfMarch.

20050429, the following pages mention yyyymmdd

20130415, the search was performed again, and the list has grown:

There are several advantages of this notation for a day on PlanetEarth:

it easily sorts into chronological order
people reading the 8 digit number recognize the pattern quickly, transparently translating it into their own native language
it gets around the confusion arising from cultures using mm/dd vs dd/mm
delimiters such as / and - confuse computers into doing division and subtraction

I have found DateStamps to be quite useful in my note keeping since long before y2k and found that rolling over from the 1900s to the 2000s was not a problem. -- ChrisGarrod

Date Stamps have been a useful pattern for years. A single number to represent a point in time, increasing monotonically, just like seconds since 19700101.000000, but far more readable by humans. Too much computerized coding of date stamps looks back at the days when space was at a premium.

We can quickly translate 20031102.1750 into 5:50 PM November 2nd, 2003. Speakers of other languages may have different names for the month, which can wreak havoc on sorting schema.

The above number sorts chronologically; this notation survived the y2k roll over. See http://humu.ucsd.edu/~garrod/y10k/ for my proposal.

Proposal? The 1997 ISO 8601 standard representation was accepted 2 years before you made your 1999 proposal. WheelReinvention?, anyone? WhatIsWithAmericanDates anyway?

Some things I've found this notation to lack:

It doesn't indicate the DayOfWeek?: but a computer could calculate that.
It doesn't indicate the TimeZone: this is perhaps more important, but most sciences which care about things with high resolution use UniversalTime? anyway.

I have a regular expression that matches date stamps with times exactly except that it allows all Februaries to have 29 days. I shoehorned it into the Perl of Ward's WikiInHyperPerl as an experiment, and I liked the results - till a co-worker deleted my wiki. 20051017.23112307 it's back, but PleaseBeGentle? at http://humu.ucsd.edu/cgi-bin/ChrisGarrod?TodaysPage. -- ChrisGarrod

If there's no requirement to store a date in a number, or you're not interested in ReinventingTheWheel, consider using one of the ISO date/time formats [http://www.w3.org/TR/NOTE-datetime]. There are formats that include DayOfWeek? and TimeZone information.

An added wrinkle, is partial dates. A time extension may not always be meaningful, and in some cases day or month may not be known. A real world example, we collect birthdates and in the population we deal with, individuals may not know anything beyond the month or sometimes the year they were born in.

To overcome some of the shortcomings listed above, how about the following complete DateStamp:

 DateStamp: 200311030945 CST Monday

Particularly since date stamps are made for the instant. Present Time, Present Time Zone, Present Day of Week. You might even want to add additional things: a name, a file or event as in:

DateStamp: 200311030948 CST Monday Edited WardsWiki Page DateStamps AnonymousOnPurpose

Or a rephrasing of DateStamp on KyleJerviss:

Original:

 KyleJerviss lasted edited this page on 10.16.2000.17.19 CST (CDT? I hate DaylightSavingsTime??)

Changed to:

 200010161719 CST Monday KyleJerviss Last Edited Homepage Remark(CDT? -- I hate Daylight Savings Time)

The decimal point between the date and the time changes the integers above: 200010161719 200311030948 into floating point numbers 20001016.1719 and 20031103.0948 My birthday is 0216, the integer, and I'm told it's more correctly 19540216.0833 Tuesday EST. The decimal point allows any degree of precision in time to still sort chronologically. Events of all sorts can be represented: Dentist appointment: 20040106.10, TransitOfVenus?: 20040608.051330 through 20040608.112551 - your timings may vary, and give you a clue about where you are.

The discontinuities in this monotonically increasing number allow recognizers to be built, just like WardsWiki recognizes when we leave out the SpacesBetweenWords and turns those items blue.

Beware the UnixTimeRollOver? 20380119.031408 (PlusOrMinus? a few LeapSeconds).

20070808.18 I listened to JamesGosling lamenting the CalendarApi of the JavaLanguage having to support the needs of historians -- The CalendarSwitchOver? from the JulianToGregorian? varied widely between Catholic and non catholic governments.

-- ChrisGarrod

20110811.15342607 Note that 2011-8-11 = 1992 and 2011/08/11 = 22.85227... 2013/4/15=33.55 Don't let those delimiters confuse the point (in time)

Delimiters separate data items while they can also serve as operators or artifactories. ItDepends on interpretations and the orders or sequence of the data items. Delimiters need not be the same: spaces, colons, semi-colons, +-/*, | \ ~ ` quotes ( a"b Or c'd a,b c,d )and many others. Mixtures and combinations can and do exist. Confusion is in the eye of the beholder. When confused I try interpretations which make some sense and fit the contents to the context. In one case it can be when and in another how much.