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Pi Day Extraordinaire

Posted by samzenpus on from the pecan-apple-or-cherry? dept.

First time accepted submitter DrTJ writes Today is Pi day. This year is a bit more extraordinary as it is 3/14/15 (in American date format). To celebrate, USA Today has posted a number of videos of kids reciting Pi, one of them to 8,784 digits. The Washington Post highlights the story of a couple who decided to make it their special day. "Donahue, 33, a Legal Aid attorney, fell for Karmel’s geeky side as soon as they met. On a beach vacation with her friends in 2012, a psychic told her, 'You are about to meet your soulmate.' Three days later, she walked into Kostume Karaoke night at Solly’s Tavern along the U Street corridor and saw a man onstage croaking out the Backstreet Boys’s 'I Want It That Way.' By the end of the night, he would be serenading her with Cake’s 'The Distance' — the song the DJ will play when they cut the pie."

18 of 107 comments (clear)

  1. Total failure on samzenpus part by Anonymous Coward · · Score: 3, Funny

    Total failure on samzenpus part to post this at 9:26

  2. Pi Day 2015: meet the man who invented Ï by auric_dude · · Score: 4, Informative

    Anglesey-born William Jones was the first person to use the Greek letter Ï for the ratio of a circleâ(TM)s circumference to its diameter. But who was this little-known figure? http://www.theguardian.com/sci...

    1. Re:Pi Day 2015: meet the man who invented Ï by camperdave · · Score: 2

      The real mystery is why the diameter was chosen instead of the more logical ratio of the circumference to the radius. Euclid would not approve.

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    2. Re:Pi Day 2015: meet the man who invented Ï by AthanasiusKircher · · Score: 2

      The real mystery is why the diameter was chosen instead of the more logical ratio of the circumference to the radius. Euclid would not approve.

      Why is the radius "more logical"? It depends on the practical use of the relationship. It seems "more logical" to use a radius as a primary circle measurement if you're using a modern mathematical definition of a set of points equidistant (by the radius) from a central point. And it seems logical to adopt this measurement if you constructed a circle in this manner.

      On the other hand, if you are confronted with an existing circle and wish to determine the circumference, measuring the diameter is more straightforward than measuring the radius. (Fix one point on the circumference, and use your straightedge, rope, whatever to find the longest distance on the opposite part of the circle.) Sure, finding the radius is simply dividing by 2, but that's an extra step.

      I don't know if this is the rationale for using the diameter in the pi definition, or if it might also have to do with the formula for circle area (pi*r^2), which is slightly simpler without the additional factor of 2, or whatever.

      Nowadays, there seem to be many good mathematical reasons for defining the ratio of circumference to radius as more fundamental. However, most of these were unknown or not primary concerns when pi was first adopted as a primary ratio. There's no "logical" priority to one or the other measurement -- it depends on practical usage for calculations, and I suspect that pi was probably just used slightly more often than 2*pi in practical calculations centuries ago.

  3. Another holiday by Anonymous Coward · · Score: 4, Insightful

    I find this one particular irrational.

    1. Re:Another holiday by ShanghaiBill · · Score: 4, Informative

      I find this one particular irrational.

      Not just irrational, but transcendental as well. A rational reason to celebrate today is that it is Albert Einstein's birthday.

  4. Re:Maybe for the English, but what about the world by rmdingler · · Score: 3, Informative
    That would be really cool if April had 31 days.

    Isn't that only true in a Romulan leap year?

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    Ernest Hemingway

  5. Hatsune Miku by Guppy · · Score: 2

    Hatsune Miku sings 1000 digits of Pi! http://www.youtube.com/watch?v...

  6. ISO 8601 by Traxton · · Score: 5, Insightful

    Today is 2015-03-14. Using any other time format is stupid and confusing. I really hate having to decode weird American standards.

    1. Re:ISO 8601 by hey! · · Score: 2

      Agreed. And I'll be celebrating Pi Day on July 22.

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    2. Re:ISO 8601 by vux984 · · Score: 5, Informative

      You "really hate" moving the year from the start to the finish?

      I know I do. For two reasons:

      Year at the front in YYYY-mm-dd format (with leading zeros on single digit months and days) lets you sort sort dates as text without having to do anything extra. That's more than a little bit convenient in a LOT of situations.

      The other issue with mm-dd-YYYY is that is indistinguishable from dd-mm-YYYY for a stupidly large number of dates; and both versions are in common use -in english speaking countries (US is mm/dd/yyyy; UK is dd/mm/yyyy so its a nightmare.) I've seen documents with both formats used interchangeably.

      If you see YYYY-nn-mm you KNOW its Year-month-day, because nobody anywhere ever uses YYYY-day-month.

  7. Re:Maybe for the English, but what about the world by BoxRec · · Score: 4, Interesting

    Nope, not even for the English, as with the rest of the World they use dd/mm/yy it's only US Americans that use mm/dd/yy

  8. Re:Maybe for the English, but what about the world by serviscope_minor · · Score: 2

    Maybe for the English, but what about the world?

    For me (french), you could say that Pi day is April 31, 2015 (31/4/15).

    Why for the English? We write the date in the same way: dd/mm[/yy]. It makes sense for fans of ISO 8601 and the Japanses who use big endian [yy/]mm/dd and of course the Americans who use the nonsensical middle-endian format mm/dd[/yy].

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  9. Re:Bubble Burst by Ichijo · · Score: 2

    Is that big-endian or little-endian?

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    Any sufficiently unpopular but cohesive argument is indistinguishable from trolling.
  10. Re:Bubble Burst by ArcadeMan · · Score: 2

    Nope, it's 2015-03-14 in the sane world.

    Keep your nonsense date format to yourself, it's almost as bad as the American one.

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  11. My bank pin number... by Rakarra · · Score: 3, Interesting

    ... is the last four digits of pi.

  12. Re: 14/3/2015 is not pi day... by Anonymous Coward · · Score: 2, Informative

    ...for the rest of the world that counts dates logically

  13. Re: 14/3/2015 is not pi day... by sgunhouse · · Score: 2

    Logical would be military date format - yyyy/mm/dd. When my European co-developer asked me for a preferred date format for commenting changes, that is the format I chose. THAT is the only format properly sortable (other than variations in separators).