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I have removed the line in the table for January 1, 0, because there are no citations. Details follow.
Symbian appears to be effectively defunct, which makes it hard to obtain information about it. I was not able to locate any documentation that seemed likely to address the epoch.
"Turbo DB" is difficult to identify. A web search returns results for seemingly different products.
MATLAB has a few different ways to represent dates. http://www.mathworks.com/help/matlab/ref/datenum.html states "The datenum function creates a numeric array that represents each point in time as the number of days from January 0, 0000. The numeric values also can represent elapsed time in units of days. However, the best way to represent points in time is by using the datetime data type." This seems to contradict the information in the article, and also makes it doubtful whether a date associated with the datenum function should be mentioned in the article when MathWorks seems to consider the datetime data type superior. Jc3s5h ( talk) 17:32, 8 April 2015 (UTC)
In the last column of the table, the line for January 1, 1, said the rational was " Common Era, ISO 8601 date 0001-01-01". Each computing system or program that uses this has a citation. Only one of the sources provide a rationale for choosing January 1, 1: Dershowitz and Reingold. They write on pages 10
The date Monday, January 1 (Gregorian), though arbitrarily chosen as our starting point, has a desireable characteristinc: It is early enough that almost all the dates of interest are represented by positive integers of moderate size.
Rather than inventing rationales that are not stated in the sources, let the readers draw their own conclusions. For dates that have characteristics that the reader has probably never noticed, it's helpful to mention the characteristic (like 1904 being the first leap year of the 20th century). But the readers are just as capable of inferring the reason for January 1, 1, as an editor.
Also, many of the other comments in the column are probably observations of the editor who added them, rather than rationale explicity stated by the creators of the systems that use them. So it might be better to relabel the column to something like "Characteristics" or "Comment". Jc3s5h ( talk) 22:09, 24 April 2015 (UTC)
how do you say this in english?
please, someone who knows, edit this in as in this article: Heidi — Preceding unsigned comment added by OsamaBinLogin ( talk • contribs) 05:42, 6 February 2016 (UTC)
In these edits User:Kevinthenerd added an epoch for the Oracle Database of January 1, 4712 BC. There are several problems with this edit.
The source says "A Julian day number is the number of days since January 1, 4712 BC. This is false. A reliable source, Richards (see footnote 4 in article) states "The Julian Day Number ... of Tuesday −4712 January 1 is 1." (p. 592) (By the way, Richards is only correct if it is understood that January 1, &minus4712, is stated in the Julian calendar, not the Gregorian calendar).
The Oracle source also gives this example:
But for the same date, the Multiyear Interactive Computer Almanac from the US Naval Observatory provides this result:
CALENDAR Date Time Day Julian Date Day-of-Year (TT) (TT) (TT) d h m s d d 1997 Jan 01 00:00:00.0 Wed 2450449.500000 1.000000
So I conclude the source is too poor to figure out what the epoch is for the Oracle Database and a better source is required. Accordingly, I have reverted the edits. Jc3s5h ( talk) 21:41, 12 May 2016 (UTC)
The source by
user:Kevinthenerd is the official source on Oracle Database, a commercial relational database software suite. There is no better source of information on the design of this software. The discrepancy noted by
User:Jc3s5h is explained therein; both of the two ways of counting are described in the source material, and the source listed by
User:Jc3s5h happens to use the other. kevinthenerd
20:21, 14 September 2020 (UTC)
Here is some original research, with commands entered into the Oracle Database software and their resulting responses. Even if Oracle Corporation is wrong about their description of their epoch, this still the way their software works. This is the best-selling database software on the market, so the relevance would be difficult to dismiss.
SQL> SELECT TO_CHAR(TO_DATE('1997-01-01', 'YYYY-MM-DD'), 'J') AS dt FROM DUAL; DT ---------------------------- 2450450 SQL> SELECT TO_CHAR(TO_DATE('1997-01-02', 'YYYY-MM-DD'), 'J') AS dt FROM DUAL; DT ---------------------------- 2450451 SQL>
kevinthenerd 20:34, 14 September 2020 (UTC)
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The result of the move request was: moved to alternative ( closed by non-admin page mover) SITH (talk) 13:14, 28 February 2019 (UTC)
Epoch (reference date) →
Epoch (date reference) – Should the undiscussed page move from
Epoch (reference date) to
Epoch (date reference) by
RTG (
talk ·
contribs) be accepted or reversed?
Jc3s5h (
talk) 03:42, 18 February 2019 (UTC)
Iffy★
Chat --
14:21, 20 February 2019 (UTC)
This is the
talk page for discussing improvements to the
Epoch article. This is not a forum for general discussion of the article's subject. |
Article policies
|
Find sources: Google ( books · news · scholar · free images · WP refs) · FENS · JSTOR · TWL |
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1Auto-archiving period: 180 days
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I have removed the line in the table for January 1, 0, because there are no citations. Details follow.
Symbian appears to be effectively defunct, which makes it hard to obtain information about it. I was not able to locate any documentation that seemed likely to address the epoch.
"Turbo DB" is difficult to identify. A web search returns results for seemingly different products.
MATLAB has a few different ways to represent dates. http://www.mathworks.com/help/matlab/ref/datenum.html states "The datenum function creates a numeric array that represents each point in time as the number of days from January 0, 0000. The numeric values also can represent elapsed time in units of days. However, the best way to represent points in time is by using the datetime data type." This seems to contradict the information in the article, and also makes it doubtful whether a date associated with the datenum function should be mentioned in the article when MathWorks seems to consider the datetime data type superior. Jc3s5h ( talk) 17:32, 8 April 2015 (UTC)
In the last column of the table, the line for January 1, 1, said the rational was " Common Era, ISO 8601 date 0001-01-01". Each computing system or program that uses this has a citation. Only one of the sources provide a rationale for choosing January 1, 1: Dershowitz and Reingold. They write on pages 10
The date Monday, January 1 (Gregorian), though arbitrarily chosen as our starting point, has a desireable characteristinc: It is early enough that almost all the dates of interest are represented by positive integers of moderate size.
Rather than inventing rationales that are not stated in the sources, let the readers draw their own conclusions. For dates that have characteristics that the reader has probably never noticed, it's helpful to mention the characteristic (like 1904 being the first leap year of the 20th century). But the readers are just as capable of inferring the reason for January 1, 1, as an editor.
Also, many of the other comments in the column are probably observations of the editor who added them, rather than rationale explicity stated by the creators of the systems that use them. So it might be better to relabel the column to something like "Characteristics" or "Comment". Jc3s5h ( talk) 22:09, 24 April 2015 (UTC)
how do you say this in english?
please, someone who knows, edit this in as in this article: Heidi — Preceding unsigned comment added by OsamaBinLogin ( talk • contribs) 05:42, 6 February 2016 (UTC)
In these edits User:Kevinthenerd added an epoch for the Oracle Database of January 1, 4712 BC. There are several problems with this edit.
The source says "A Julian day number is the number of days since January 1, 4712 BC. This is false. A reliable source, Richards (see footnote 4 in article) states "The Julian Day Number ... of Tuesday −4712 January 1 is 1." (p. 592) (By the way, Richards is only correct if it is understood that January 1, &minus4712, is stated in the Julian calendar, not the Gregorian calendar).
The Oracle source also gives this example:
But for the same date, the Multiyear Interactive Computer Almanac from the US Naval Observatory provides this result:
CALENDAR Date Time Day Julian Date Day-of-Year (TT) (TT) (TT) d h m s d d 1997 Jan 01 00:00:00.0 Wed 2450449.500000 1.000000
So I conclude the source is too poor to figure out what the epoch is for the Oracle Database and a better source is required. Accordingly, I have reverted the edits. Jc3s5h ( talk) 21:41, 12 May 2016 (UTC)
The source by
user:Kevinthenerd is the official source on Oracle Database, a commercial relational database software suite. There is no better source of information on the design of this software. The discrepancy noted by
User:Jc3s5h is explained therein; both of the two ways of counting are described in the source material, and the source listed by
User:Jc3s5h happens to use the other. kevinthenerd
20:21, 14 September 2020 (UTC)
Here is some original research, with commands entered into the Oracle Database software and their resulting responses. Even if Oracle Corporation is wrong about their description of their epoch, this still the way their software works. This is the best-selling database software on the market, so the relevance would be difficult to dismiss.
SQL> SELECT TO_CHAR(TO_DATE('1997-01-01', 'YYYY-MM-DD'), 'J') AS dt FROM DUAL; DT ---------------------------- 2450450 SQL> SELECT TO_CHAR(TO_DATE('1997-01-02', 'YYYY-MM-DD'), 'J') AS dt FROM DUAL; DT ---------------------------- 2450451 SQL>
kevinthenerd 20:34, 14 September 2020 (UTC)
Hello fellow Wikipedians,
I have just modified 3 external links on Epoch (reference date). Please take a moment to review my edit. If you have any questions, or need the bot to ignore the links, or the page altogether, please visit this simple FaQ for additional information. I made the following changes:
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Cheers.— InternetArchiveBot ( Report bug) 04:43, 25 December 2016 (UTC)
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Cheers.— InternetArchiveBot ( Report bug) 22:28, 26 July 2017 (UTC)
The result of the move request was: moved to alternative ( closed by non-admin page mover) SITH (talk) 13:14, 28 February 2019 (UTC)
Epoch (reference date) →
Epoch (date reference) – Should the undiscussed page move from
Epoch (reference date) to
Epoch (date reference) by
RTG (
talk ·
contribs) be accepted or reversed?
Jc3s5h (
talk) 03:42, 18 February 2019 (UTC)
Iffy★
Chat --
14:21, 20 February 2019 (UTC)