20100103

Calendrier- French Revolution Calendar

I posted earlier about decimal time iPhone apps.  I had also searched for an app for the French republican/revolutionary calendar, as the calendar was tied together with decimal time.  I even searched the French word "calendrier", but did not find one.  This calendar was used from 1793 to 1805, and replaced the 7-day week with the 10-day décade, with exactly three décades (i.e. 30 days) a month and five or six extra days at the end of the year, which began on the autumnal equinox in September.

Well, now there is an app for that, too, released December 20 (MJD 55185).  It's called Calendrier- French Revolution Calendar by Kawasemi Corp. (José Luis Martín Mas) and costs $1.99.

I thought that name was familiar; he's the same one who made the Mac Dashboard widget, with whom I've communicated before.  As I remember, instead of the years always starting on the equinox, he uses an odd rule that every fourth year be a leap year, except for years divisible by 128.  That means that in this app the current year CCXVIII (218) started on 2009 Sept. 23 (55097) even though the equinox was on Sept. 22 (55096).  However, the next autumnal equinox is on Sept. 23, so the two versions will coincide the next republican year, although some use yet a different version, with a leap year rule similar to the Gregorian calendar, that starts on Sept. 22.  BTW, today's French republican date would be 13 Nivôse CCXVIII, Tridi, Décade 2, according to the app, or Quartidi, 14 Nivôse, according to the other versions.

It also displays the decimal time, like the other apps, although digital only.  That makes a total of four apps which display French decimal time.

MJD 55199.6
Quartidi 14 Nivôse an CCXVIII à 6h6 t.m.P.

16 comments:

  1. I'm Jose Luis Martin, the author of Calendrier. Thanks a lot for your post and comments, I hope it will make the app more known. :)

    About the leap years rules, yes, in this first version I'm using the 4/128 rule, but in next version, that I hope to have ready in a few weeks, I will adopt the Romme rule, that is, starting from Rev year 20, calculate the leap years like in the Gregorian Calendar.

    After much consideration, I find it the most efficient rule, and in a sense, the most reasonable with a historic sense of justice. Right before his death at the guillotine, Romme was drafting a proposal to adopt the Gregorian rules for leap years. He was executed before being able to submit his proposal, and so the only "legal" rule should be the equinoctal one... but considering that Romme was the father of this calendar, and that his intention was to make this change, he deserves that I use it.

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  2. Perhaps you could provide the different versions as an option in settings.

    My algorithm was basically to add the average period between autumnal equinoxes, 31,556,907 seconds. I tested it against the actual dates since 1792 until far into the future. I'll send you the code.

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  3. I've always favoured the Brumaire system, so I'll echo what John said, in having multiple versions of the calendar to suit the user. I would've hoped Brumaire would have had an app out by now, but at this point, I'm happy with anything that comes out for my iPod touch. :)

    I could think of a few other ideas (notably, a grid representation of the current FRC month, like most conventional calendars; options for the clock to display TMP, UTC and local time, calendar adjusted accordingly; alternate names for months/days that have been applied/adopted... You get the idea! ;) ), but for now, it's a plus. :)

    d.m.f.
    (who has DeciTime and Internet Beat on his iPod already...)

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  4. I should also add that the Revolution and the Republic actually had different calendars, and to be more correct, this is the calendar of the French Republic, sometimes called the "Calendar of Reason".

    Now, if someone made a Roman-numeral decimal clock... ;) There are only a couple Roman numeral clocks for the iPhone/iPod touch, NO Julian/Roman calendar, and certainly no Coligny Celtic calendar, all of which I wish I had right now... (The two clocks only display in landscape mode-- Since I have my iPod on its charging base most of the time, I prefer the standard portrait mode, a reason, ironi9cally, why I haven't grabbed MetricClock yet...)

    d.m.f.

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  5. I haven't grabbed it, either, but the description for MetricClock says, "The clock also rotates with the iPhone/iPodTouch."

    One thing I noticed with some of these apps is that there is no option to disable auto-locking, so that the screen won't turn off, like most of the regular clock apps have.

    PerfectClock has Roman numerals with portrait mode, and it's free. Not decimal time, though.

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  6. I simply disable auto-locking in Settings. :)

    I'll check PerfectClock, but last I saw, if I'm not mistaken, it only ran landscape... But I will check into it. :)

    BTW, Internet Beat, when it shows centibeats in landscape mode, appears only to refresh once every standard second, and oftentimes-- if you pardon the bad pun- skips a (centi)beat... :) I have brought that up with the guy who made it, but it's never been updated.

    d.m.f.

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  7. It turns out that it's no longer free, but the lite version has a couple of Roman portrait clocks, although a bit off-beat.

    Some decimal time programs have a bug caused by the fact that they're converting a standard time, with one-second precision, but decimal seconds increment more quickly. It's like the difference between lunar and solar months; occasionally you get a blue moon when two new moons happen in the same solar month, as happened last week. That's why my algorithm uses Unix time in milliseconds.

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  8. BTW, there are some apps which use the Julian calendar, although they're mostly in Greek, and don't seem to display the entire month. Just search for "orthodox calendar".

    But I imagine you're looking for one in Latin, with 8-day weeks, calends/nones/ides, etc.

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  9. DeciTime doesn't seem to have the same refresh issue, which is nice. :)

    And yes, I am looking for the traditional Latin form. :)

    On the same vein, combining the two (FRC and liturgical calendars), I await the day of the traditional Ethiopic and Coptic calendars making their way to the app store...and hopefully free. (Boy, do I wish for alot, don't I? :D )

    (Much further off tangent, there is an app now for Martian times as observed by the Spirit & Opportunity rovers... Yes, it's free.)

    d.m.f.

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  10. iCoptic was released a couple of days ago. The Ethiopian Date app was released on Thanksgiving. The latter is $0.99, but iCoptic is $9.99. It must be worth it, though, with 6 5-star reviews already.

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  11. I have 3 decimal time clock apps on my iPod Touch: French clock, DeciTime and iBeat. The French Calendar app seems cool. I better give it a try.

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  12. iDateConvert by Which.Lilith displays dates for many different calendars, including two versions of the French calendar, and the Roman calendar in Latin, as well as Coptic, Egyptian and Ethiopian. It's $2.99.

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  13. I really like the application.

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  14. This comment has been removed by a blog administrator.

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    Replies
    1. I blanked your comment by accident. You said, "Hello sir please bring out a version for Android, Thanks!"

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