Talk:Calendar date

From Wikipedia, the free encyclopedia
Jump to: navigation, search
WikiProject Time  
WikiProject icon This article is within the scope of WikiProject Time, a collaborative effort to improve the coverage of Time on Wikipedia. If you would like to participate, please visit the project page, where you can join the discussion and see a list of open tasks.
 ???  This article has not yet received a rating on the project's quality scale.
 ???  This article has not yet received a rating on the project's importance scale.
 

Weeks and Gregorian Calendar[edit]

I would like to show a minor view of mine on writting of today's dates. I am fully awared with ISO 8601 standard. Recently I prefer to writte dates in these Mayan like form.

For example dates of current week I write:

0 Sunday   [2002.02.24]
1 Monday   [2002.02.25]
2 Tuesday  [2002.02.26]
...
6 Saturday [2002.03.02]

It is strange, yes - but ISO 8601 in a sence goes the same way. Mayan have two weeks with different number of days and I know why they write in such strange form which is, astronomically speaking, perhaps the best and the righteous one. We have only one week, with 7 days, first would be numbered as Mayan do 0. And all in brackets ([]) is noncycleing but linear increasing numbers for years, set of 12 months with selection from {28,29,30,31} and of course in the end - days all numbers in decimal system. Mayan used kindly different number systems. How long will it take we will adopt ISO 8601 in fully. I am sometime nowadays all confused. What do you think?
XJam following ISO 8601 let us write just 2002-27-02 where leading zeroes must be written. ** This is not ISO !! ** *** Yes you gotcha me, of course 2002-02-27 is correct - that is what I was talking about -- confusions, sorry --XJam 6 Saturday [2002.03.02] (0)***

If you think of it, the Mayan, the ISO, the Chinese, the Japanese simply use the natural way to tell time, i.e. in a natural progression from the longer to the shorter period, naturally, year, then month, then day, then hour, then minute, then second. Even the European notation of Day, Month, Year is natural but just in the opposite order. Only the US tries to be different and put in the Month, Day, Year unnatural order.

So one can start the week on a Sunday, but number the other days of the week by the number of days it comes after Sunday.

Sunday 0, 
Monday   1, Tuesday 2, Wednesday 3
Thursday 4, Friday  5, Saturday  6.

This looks like a compromise between starting the week on Sunday (actual start) and starting the week on Monday (numbering of non-Sundays).

==> Note that the Hebrew language word for Sunday is "Yom Rishon" or "1st day," relating that it is the first day after the Sabbath. It goes through Friday as "Yom Shishi" or "6th day," and the 7th is "Shabbat." This date system is still in use for legally binding Jewish religious documents such as marriage contracts. User:Batya7 2009.02.24


If one starts with week with a Sunday then a symmetry occurs around the year 2000.

Below for each year, I list the number of days in the part-week at the start of the year, the number of whole weeks within the year, then the number of days part-week at the end of the year.

1997 4 days + 51 weeks + 4 days
1998 3 days + 51 weeks + 5 days
1999 2 days + 51 weeks + 6 days
2000 1 day  + 52 weeks + 1 day
2001 6 days + 51 weeks + 2 days
2002 5 days + 51 weeks + 3 days
2003 4 days + 51 weeks + 4 days

This symmetry applies to all years not just those listed e.g.

1900 6 days + 51 weeks + 2 days
2100 2 days + 51 weeks + 6 days

For weeks beginning Monday or any other day of the week, there is no such symmetry around any year at all.

User:Karl Palmen


Uph Karl, very interesting indeed. I must say I do not uderstand your table in full. Can you please give some more explanation on it? What really (2002 5 days + 51 weeks + 3 days) means? Does this mean that current year 2002 has 51 weeks and ('plus what)?

Yes I have understood that correctly. Thank you Karl for clearing this out. This year's 2002 first part-week is:

[2] Tuesday   [2002.01.01]
[3] Wednesday [2002.01.02]
[4] Thursday  [2002.01.03]
[5] Friday    [2002.01.04] and the last day of the 1st part-week
[6] Saturday  [2002.01.05] --> and all together is 5 days.

Then we have 51 "ordinary" weeks and the last part-week:

[0] Sunday    [2002.12.29] (First day of the last part-week :-)
[1] Monday    [2002.12.30] and finally 
[2] Tuesday   [2002.12.31] --> that gives us 3 days 

so 2002 have: 5 + 51*7 + 3 = 365 days.

Nice. --XJam 1 Monday [2002.03.04] (0)

Correct User:Karl Palmen


Strange property of Gregorian calendar, don't you think and hard to calculate days between events in it, too. On my desk working calendar there is written that 2002 has 52. working weeks (fixed day (or closing date) weeks again according to ISO 8601) and 1st working week of 2003 starts on 1 Monday [2002.12.30]. 1st working week of 2002 starts again on 1 Monday and that is [2001.12.31]. In fact I do not like Gregorian calendar a lot, but I must use it. Tzolk'n is much much more thoughtful and who knows more usefull. I do not like Gregorian calendar too because astrologists calculate their strange horoscope and fated tables from it, and they say they're some experts on something that doesn't exist, astronomicaly speaking. (I mean a sky map, which because of precession of equinoxes does not fit with a real one and such). --XJam 5 Friday [2002.03.01] (0)

Astrologers would may also get it wrong if they use the Gregorian calendar literally. For example the start of the sun-sign of Aries is reckoned to occur at at the March equinox and also on March 21, yet in 2096, the equinox will be on March 19. --User:Karl Palmen



  • I have no problem with using ISO 8601 for dates and times, even though the usage in relation to days of the week and linking weeks to years seems a bit strange. The purpose of a standard is to get everybody to mean the same thing when they write. I can't say that I understand the references above to the Mayan calendar - but that's the entire problem with it: few people will. It must be added too that the numbering of the weeks and the days in the week has a limited application outside of finance. A day can be completely defined without knowing what the day of the week is. Using the Gregorian calendar has absolutely nothing to do with the validity of horoscopes. I don't need to believe in God and Jesus to accept that we are in the Gregorian year 2002. Eclecticology
    • Yes for days there's enough ISO codeing. It is enough although a little bit hard to calculate it by hand. We humans like to calculate by hand(s) which have 10 fingers, so not too long week is just fine for us. It is very human, as we say, why to be symple if it can be complicated and so Mayan combined Tzolk'in and Haab where there are in Tzolk'in 13 numbered days intermeshed with 20 named days and in Haab or vague year is a 365 day period of 18 months of 20 days each, followed by one 5 day period (Wayeb). Now days are harder to calculate.

      I've forgotten to say that above record is just my personal view and a little bit of self contentment. I am not trying to change any present or future standards. About Mayan there is not so much to understand in fact. Their calendar is so symple and yet so 'almost' perfect. With the 13th (leading) Mayan's cycle or bak'-tun I just wanted to emphasize their believes in cycleing of time - posible property of real (cosmological) time - which is not implemented in our year's notation. They had used a term similar of our year (Earth's revolution around the Sun, tropical year) in 3rd place of their notation as tun from bak'-tun. For shure they must had been awared in some way of Earth's revolution. Recently I've translated and adopted (now perhaps famous) John Major Jenkins' article The How and Why of the Mayan End Date in 2012 A.D and I must say his researches in this field persuaded me about general significance of Mayan calendar system of far past and of imminent present time, because we are heading toward such strange years as Clarke's 2001, Clarke's 2010, Mayan's 2012, Clarke's 2061 are. Their calendar, according to our present knowledge of Mayan's astronomy, was derived almost entirely from horizont astronomy mainly by observing the apparent motion of 'planet' Venus and Sun and such.

      I agree about validity or non-validity of horoscopes. But they (Greek or Chinese one at most) are 'studied' mainly in Western calendar system (Julian, Gregorian). Mayan also used (mainly Tzolk'in) to do 'horoscopics' and their descendant in Jenkins' 'dream land' Gvatemala still do. But hereby I do not want to say no other words about 'horo-hocus-pocus' because I respect all what Samuel Beckett had said on this topics.

      I also agree and salute natural progression from longer to shorter period of any calendar. Yes strange why Europeans like smaller things first. Americans must have heard to put a year on the last place from Indian natives, ha, ha. Legalisation fi di ganja herb - Do you love the music, yeah, reggae music ruffin' inna Japan Salute and out. --XJam 6 Saturday [2002.03.02] (1st ed.)

Japanese Calendar[edit]

In Japan, all official documents are required by law to use the Japanese imperial calendar date format. For example, the year 2001 is known as Heisei 13 (平成13年). Similar, in Taiwan, the year 2002 is known as Min-guo 91 (民國九十一年).

Can you justify this is true? Where did you get this idea? -- Taku 03:04 Feb 26, 2003 (UTC)

Transition dates near start of calendar[edit]

What about giving an example of one of the dates from the period when the calendar was being adopted and the new year shifted (from March to January), resulting in year formats such as 1680/81, to mean 1680 if new year is counted in March, but 1681 if new year is counted in January ?


external links[edit]

removed * Easy Date Converter Windows software for conversion of Gregorian, Julian and ordinal dates and for calculations with them as it is available at the bottom of the other link to hermetic.ch

Long Format date[edit]

Is there any usage of ISO8601 while writing long date format. I know that ISO concerns only in numeric representation.

Globalization[edit]

The internet has allowed date formats similar to other nations is diffusing one after another. Examples of these include some of the "American format" talk in other countries, the date appearaing occasionally before the month in the US has somewhat increased, and use of a period in endian forms as a separator in the U.S. as of late (such as CBS Evening News, The Today Show, FOX News, and the Baltimore Sun newspaper, many recent films.) The month day year format stil exists though. Some confusion, especially on international english websites like Youtube, lead to some confusion, especially on the first 12 days of every month. Maybe a separate section could discuss this influence.

Month and year[edit]

I miss a section about dates that leave out the day, e.g. "12/2010" vs. "2010-12". This should be included into this article. 92.231.85.219 (talk) 08:07, 6 July 2011 (UTC)

Binary Representation (computer) - what about all the other OS?[edit]

I'm slightly bemused by the sole entry in this section referring exlusively to iOS. Are all other OS dead already? 212.159.59.5 (talk) 09:41, 14 January 2012 (UTC)

merge[edit]

Currently there are several articles almost entirely composed of various date notations -- various ways to say or write or otherwise specify some particular day.

I suggest we merge together -- into one or two articles -- some or all of: "calendar date", "date and time notation", "date (metadata)", "date format by country", and "ISO 8601 usage". --DavidCary (talk) 17:01, 13 December 2012 (UTC)

Popularity of formats[edit]

In the article, I stated:

"The most popular format is YYYY-MM-DD (e.g., 1999-05-31), which is the international standard, followed roughly by DD/MM/YYYY. However, the class of middle-endian formats (day, then month, then year; including D/M/YYYY, DD.MM.YYYY, etc.) is a lot more popular than the class of all other formats (including YYYY-MM-DD, MM/DD/YYYY, etc.)."

An editor thought that this statement is contradictory (in addition to not being directly sourced).

Here I give an explanation for this statement, and give some references.

On the popularity of various date formats, I calculated rough statistics based on the list of countries by population and date format by country articles and various other country-articles and external sources for which the date format by country article is incomplete (for some countries, the article tells the endianness of the country's format, but not the full format itself). I ended up with:

1. YYYY-MM-DD — >1.6 billion users (the greatest contributor to this statistic is China)
2. DD/MM/YYYY — <1.5 billion users
3. DD-MM-YYYY — <1.5 billion users (the greatest contributor to this statistic is India)

Others formats are even less popular. (Note: DD/MM/YYYY is slightly more popular than DD-MM-YYYY.)

However, if we combine all little-endian date formats (DD/MM/YYYY, DD-MM-YYYY, DD.MM.YYYY, D/M/YY and so on), then that gives a format class that has a popularity of >4 billion. Since there are only 7 billion people, by necessity, any other format class, that does not include any little-endian format, must have a popularity of <3 billion. So this is true even for the class of all non-little-endian formats.

Unfortunately, I could not find a raw statement that "the 2nd most popular format is DD/MM/YYYY"; but a source that is already referenced, contains:

"[The YYYY-MM-DD format] is identical to the Chinese date notation, so the largest cultural group (>25%) on this planet is already familiar with it.",[1]

which we can translate to "the YYYY-MM-DD is the most popular format (or at least was in 2004)". — Preceding unsigned comment added by 78.92.206.43 (talk) 06:58, 14 June 2013 (UTC)

The Microsoft source that supports the claim for China in the "Date format by country" article indicates several different formats, which makes one wonder about the Kuhn source. I'm inclined to think the Chinese tend to use numerical dates and the order year, month, day, but I'm not persuaded about the form with the dash as the separator being most popular.
In many English speaking countries, there is mixed use of a numeral for the month or a word for the month; I'm not sure what the balance is between words and numerals in other countries. But this fact prevents you from simply assuming that, for example, mm/dd/yyyy is the favorite format of 300 million Americans. Perhaps 50 million prefer month dd, yyyy and 20 million prefer dd month yyyy. Unless someone has done a poll, we don't know. Jc3s5h (talk) 01:00, 15 June 2013 (UTC)
I think the problem with our IP editor's comments lie in the words "... I calculated rough statistics..." That is synthesis, and hence not acceptable here. As Jc3s%h points out, creating such "rough statistics" involves making a lot of assumptions. I could make a whole different bunch of assumptions and come up with very different numbers. There really is no point trying to include this content. HiLo48 (talk) 01:08, 15 June 2013 (UTC)
Perhaps Kuhn is a root source.
Perhaps "all-numeric" should have been added for clarity, to exclude long and intermediate formats.
By rough statistics, I mean that I first considered the countries with the most population (for China, I assumed YYYY-MM-DD, for India, I assumed DD-MM-YYYY, and for Brazil, I assumed DD/MM/YYYY), and added into consideration smaller countries, until it was apparent that the YYYY-MM-DD format's popularity-lead would not be broken, even if the non-considered countries all used the DD/MM/YYYY format. I stopped counting at about 1.7 billion for YYYY-MM-DD, 1.4 billion for DD/MM/YYYY, 1.3 billion for DD-MM-YYYY, less for various other formats, and much less for "the non-considered class of formats". However, if "some" people in China modify the format slightly, then we can also say the same regarding the other most significant contributors: India and Brazil. — Preceding unsigned comment added by 84.0.144.143 (talk) 05:14, 15 June 2013 (UTC)


Cite error: There are <ref> tags on this page, but the references will not show without a {{reflist}} template (see the help page).