# Talk:Determination of the day of the week

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## Reverts to the Revised Julian calendar

I'm involved in a lot of other issues right now, but I want to comment on many recent edits to Determination of the day of the week#Revised Julian calendar before I lose the thread. See edits by [1] [2][3][4]

Our article states 27 January RJC AD 8315 is a Tuesday. My hand calculation via another method agrees with Tuesday. (That said, I believe the offered procedure miscalculates the correction for some years, but I need to investigate that further.)

The reverts claim 27 January RJC AD 8315 is a Wednesday. As proof, an edit comment states "This link shows this Jan 27, 8315 date as Wednesday. http://moodle.pnwu.edu/calendar/view.php?view=month&course=1&time=200228832000".

Following that link does show 27 January AD 8315 is a Wednesday, but the calendar shown is not the Revised Julian calendar but rather the Gregorian calendar.

The text of Determination of the day of the week#Revised Julian calendar states that the Revised Julian and Gregorian calendars match from AD 1923 until AD 2800. The date in question falls outside of the matching interval. The table given at Revised Julian calendar#Arithmetic shows that the RJC and the GC differ by +1 day in AD 8315. In other words, a date in the Gregorian calendar is one day later than the same date in the Revised Julian calendar. That's why the Gregorian calendar is saying it is a Wednesday. The date in the RJC is the previous day, which would be a Tuesday.

The basic mistake is not recognizing the difference between the Revised Julian calendar (RJC) and the Gregorian calendar (GC).

Glrx (talk) 04:33, 12 June 2016 (UTC)

Wow. Thanks for the education about the RevisedJulianDate issue. I should have realized that the formulas that work until 2800 will have to be revised as that 11 second error keeps accumulating. Tuesday it is then for RJDate!! Thanks for being understanding about my newness to Wikipedia. After reading the history page I do think there is a need to clean up this page but that is a low priority I suppose. It is dense and hard to follow. JackieDander — Preceding unsigned comment added by JackieDander (talkcontribs) 21:43, 1 July 2016 (UTC)