Calculate the day of the week for any date in your head

Re:Calculate the day of the week for any date in your head by stkdump on Wednesday January 01, 2020 @06:07AM (#21927593)

You can skip the leap year info completely if you consider both January and February as belonging to the previous year. That makes sense as the additional day (Feb 29) is at the end of Februry.

Last year Pi Day was Thursday, this year Saturday.

So the general rule then is: March 14th, April 4th, May 9th, June 6th, July 11th, August 8th, September 5th, October 10th, November 7th, December 12th, January 2nd, February 6th are Pi Days.

Edit: another nice rule is that usually Pi-Days increase by 1 each year (2 in leap years), so next year it will be Sunday, then Monday, Tuesday, Thursday (leap year), Friday, etc.

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Re:Calculate the day of the week for any date in your head by netsharc on Wednesday January 01, 2020 @12:32PM (#21929143)

But why do you call them Pi-Days? Pi Day is 3/14 because that's somewhat similar to 3.14, which is Pi to 3 significant digits..

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Re:Calculate the day of the week for any date in your head by stkdump on Wednesday January 01, 2020 @01:13PM (#21929468)

They are the same weekday as 3/14 and it makes a little more sense than 'Doomsday', which the article chooses.

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Re:Calculate the day of the week for any date in your head by netsharc on Wednesday January 01, 2020 @02:47PM (#21930087)

I vehemently disagree, you can't just redefine Pi-Day to what you want. Pi Day is 3/14, not 4/4 or 6/6.

As for calling it Doomsday, well, it's from the title of the paper about the algorithm, by the man who invented it, the famous John Conway: https://en.wikipedia.org/wiki/Doomsday_rule

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Re:Calculate the day of the week for any date in your head by stkdump on Wednesday January 01, 2020 @11:52PM (#21933119)

I didn't come up with this. According to the article, Roman Weil of Princeton teaches the same.

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