[Historic] The "time" of time

Aaron Straup Cope aaronofmontreal at gmail.com
Sat Aug 25 22:58:59 BST 2012

One of the things that a few of us in the museum world have been talking 
about is boiling any given date in to 4-5 individual fields:

* A display date, like "c. 12c crazy times"

* An ISO-8601 date string

* A boolean indicating BCE

* A granularity, which is little more than a label/pointer to a function 
that calculates a date range for a starting (ISO-8601 + is_bce).

Flickr used "granularities" to express month, year, decade and 
eventually circa for photos in the Commons. Circa was simply decided 
from on high (read: me) to mean 5 years on either side of a date but you 
could make the rules governing date in and dates out as complex as you 
wanted. They just need to be documented somewhere.

* A function for encoding/decoding one end of granulatity(iso8601, 
isbce) as a signed (big) int for storing the above as plain numbers for 
doing fast date ranges in a database. The idea is that 0 would continue 
to mean Jan 1 1970 and that anything before it would become a negative 

An added bonus would be something that could take (iso8601, bce, 
granularity) and pre-generate as good a display date as possible.

It's still mostly talk although the talk has started to include words 
about grant money to find someone to do the encoding/decoding. The last 
thing I want to do (or can) is suffer that kind of date math.

But it would be super useful across a range of fields, I think.

On 8/24/12 12:28 PM, Jeff Meyer wrote:
> Mikel's spherical Mercator thread triggered another question for me - if
> we were to add the concept of time to any map-/geo-related objects, how
> would we express that time?
> Does anyone have a recommendation for this?
> ISO-8601 is often referenced (and maligned) as the relevant standard,
> begging the questions:
> - Which ISO-8601?
> - How to handle BC / negative years?
> - Why use such an odd convention (YYYY-MMM-DD... big Endian?)?
> I believe the OpenLayer guys have run into some interesting challenges
> working with this format.
> - Jeff
> https://github.com/openlayers/openlayers/pull/413
> --
> Jeff Meyer
> Global World History Atlas
> www.gwhat.org <http://www.gwhat.org>
> jeff at gwhat.org <mailto:jeff at gwhat.org>
> 206-676-2347
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