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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."

58 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. How Irrational by Anonymous Coward · · Score: 1

    "a psychic told her, 'You are about to meet your soulmate.'"

    How... irrational.

    Wait, why are they getting hitched on Pi da... oohhh. I get it now.

  5. Maybe for the English, but what about the world? by Eloking · · Score: 1

    For this reason, I found it a little dumb to consider this the "Pi day" : https://thebehaviorallab.files...

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

    --
    Elok
  6. Tau Day by Anonymous Coward · · Score: 1

    Pi is wrong.
    True mathematics nerds will celebrate on June 28, 2031

  7. 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

  8. Hatsune Miku by Guppy · · Score: 2

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

    1. Re:Hatsune Miku by Al+Al+Cool+J · · Score: 1

      That's the short "radio" version. The hour-long 10,000 digit version I think has greater impact. :-)

  9. Re:Maybe for the English, but what about the world by Eloking · · Score: 1

    That would be really cool if April had 31 days.

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

    Omg yes you're completly right. Silly mistake and it mean it would be January 3, 2041 (3/1/41) instead. Oh well..

    --
    Elok
  10. I hate Pi Day. by Anonymous Coward · · Score: 1

    So much. It's just a naturally occurring number, not even particularly special. It doesn't commemorate anything. It's the exact same thing as all of the stoners going "OMG! It's 4:20 LOL!"

    1. Re:I hate Pi Day. by rmdingler · · Score: 1

      So much. It's just a naturally occurring number, not even particularly special.

      It is this year. It was Pi to ten digits at 09:26:53 this morning.

      --
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      Ernest Hemingway

    2. Re: I hate Pi Day. by Anonymous Coward · · Score: 1

      Only if you arbitrarily place and then edit the digits used. Non-standard, drop leading 20 and leading 0.

      Childish.

    3. Re: I hate Pi Day. by Zeroko · · Score: 1

      date '+%-m.%d%y%-H%M%S'

    4. Re:I hate Pi Day. by billstewart · · Score: 1

      There was a good reason for 4:20 (though not particularly for 4/20.) It was when all of the Waldoes were done after-school activities and could get together and smoke before going home or riding bikes up and down the mountain or whatever.

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  11. 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 ArcadeMan · · Score: 1

      There's only 12 months in a year and ISO 8601 only allows "-" for the separator.

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    3. 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.

    4. Re:ISO 8601 by DNS-and-BIND · · Score: 1
      Ah, yes, the lighthearted story about a bit of amusing geek-friendly numerology is visited by the unsmiling European who - as always - delivers a stern lecture about How You Americans Are Always Wrong.

      It never gets old I tell ya, humorless jerks coming into a thread and crapping in the punch bowl.

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    5. Re:ISO 8601 by Brett+Buck · · Score: 1

      Oh, sure, who doesn't like to hear this?Between this, and "metric system is better lectures" makes me feel small. Almost makes me overlook that fact that none of these wise-asses would exist, except for us.

    6. Re:ISO 8601 by swell · · Score: 1

      Now take that to the next step...

      When you use the format YYMMDDHHMMSS.nn as I have done for decades, sorting remains easy and you require fewer characters/bytes/keystrokes. Why slash or hyphenate? Use as many digits as necessary but always include at least the year and month so that your meaning is clear. At a glance you can see that you are looking at a date, You won't have any ambiguity in most cases. I have hundreds of files (already in March) labelled with 15 followed by 01, 02 or 03. I don't expect to live until year 2115, so I don't need the 20 to designate this century, but business, government and young people should include that too.

      --
      ...omphaloskepsis often...
  12. 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

  13. 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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  14. Re:Bubble Burst by Ichijo · · Score: 2

    Is that big-endian or little-endian?

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  15. Japan! by ArcadeMan · · Score: 1

    Don't forget that today is also Oppai Day!

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  16. 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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  17. Trivia by jchevali · · Score: 1

    Who cares.

    1. Re:Trivia by wonkey_monkey · · Score: 1

      Other people. Why does that so offend you that you actually had to go out of your way to let people know that you don't care?

      --
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  18. Re:Bubble Burst by Art3x · · Score: 1

    It's 14/3/2015 in the sane world.

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

    How do you say it? 3/14/2015 goes along with how Americans say dates: "March third, Twenty Fifteen." I suppose the European way, 14/3/2015, with its nice descending specificity, corresponds to saying "The fourteenth of March, Twenty Fifteen," or even as I've heard it said, "Fourteen March, Twenty Fifteen."

    But in normal conversation do you say anything like 2015-03-14, like, "I will see you again on Twenty Fifteen, March 14"?

  19. Re:Bubble Burst by Art3x · · Score: 1

    It's 14/3/2015 in the sane world.

    14 has no meaning outside of the month. 14 literally means the 14th day of the month. The month is the context. The fourteenth day of what? March. So when people say dates, it is perfectly normal to begin with the context and then the day. "What's the date?" "It's the month of March, and we are in the 14th day of it."

    Why not then begin with the year, since that is the even broader context? "The year is 2015, in the month of March, on the 14th day." Because when people make appointments with each other, they do not normally make them more than a year ahead. "When shall we meet again?" "April 20th." It would be so unusual to make an appointment for April 20 of some other year, that we leave off the year. When we have to give a year --- "When was the Battle of Antietam?" --- we are already in the habit of saying month and then day, so we stick with it, and append the year, "September 17, 1862."

  20. Re:Maybe for the English, but what about the world by reboot246 · · Score: 1

    We Americans write it that way because that's the way we say it.
    Compare:
    "Today is March fourteenth."
    "Today is the fourteenth of March."

    Four words are more efficient that six words, and it just sounds more natural in speech.

  21. Happy Birthday Eli by rossdee · · Score: 1

    and a happy birthday to my nephew Eli
    but I am not sure if he still reads slashdot

  22. Re:Bubble Burst by ArcadeMan · · Score: 1

    People don't use the year in normal, vocal conversations.

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  23. Pi is 3.1416 by loufoque · · Score: 1

    Good try, but Pi is 3.1416, not 3.1415.

    1. Re:Pi is 3.1416 by tehlinux · · Score: 1

      Pi is exactly 3!

      --
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    2. Re:Pi is 3.1416 by Anonymous Coward · · Score: 1

      3.1416 is an approximation produced by rounding. 3.1415 is an approximation produced by truncation.

      Both are accurate enough for most purposes.

  24. Re:Maybe for the English, but what about the world by xvan · · Score: 1

    I haven't seen the YY notation since 1999. I don't know the rest of the world.

  25. Re:Maybe for the English, but what about the world by Livius · · Score: 1

    "Today is Fourteen March."

    Even fewer letters!

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

    ... is the last four digits of pi.

    1. Re:My bank pin number... by Anonymous Coward · · Score: 1

      My pin number is the last 11 digits.

      Don't ask me, seems pretty irrational to have such a large number for a pin.

  27. Re:Maybe for the English, but what about the world by newcastlejon · · Score: 1

    People mainly use yyyy/mm/dd because sorting by name will also put entries in date order.

    --
    If God forks the Universe every time you roll a die, he'd better have a damned good memory.
  28. Re: 14/3/2015 is not pi day... by Anonymous Coward · · Score: 2, Informative

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

  29. Re:Maybe for the English, but what about the world by Demonoid-Penguin · · Score: 1

    We Americans write it that way because that's the way we say it. Compare: "Today is March fourteenth." "Today is the fourteenth of March." Four words are more efficient that six words, and it just sounds more natural in speech.

    Real life example:

    • Q. What's the date?
    • A. The 14th.

    P.S. The USA is not the world, and time might be a concept but...

  30. Re: 14/3/2015 is not pi day... by jenningsthecat · · Score: 1

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

    Came here to say this but you beat me to it. So I'll just add that if we're going to use the American system of dating, (and not add in the hours, minutes, and seconds), then Pi Day is NEXT year. Pi rounded to four decimal places is 3.1416.

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  31. 22nd July by Roger+W+Moore · · Score: 1

    The 22nd of July works for the rest of the word. 22/7 is actually very slightly more accurate than 3.14.

  32. Re: 14/3/2015 is not pi day... by Zeroko · · Score: 1

    Logically would be 2015/3/14. Or rather, that is big endian & the other way little endian. I suppose 3/14/2015 is, then, American endian...

  33. Oh the irony! by Roger+W+Moore · · Score: 1

    We Americans write it that way because that's the way we say it.

    Except that you don't always! You use the American date format most of the time except when referring to "the fourth of July" then, or all the times, you always use the English format.

  34. 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).

  35. Re: 14/3/2015 is not pi day... by graphius · · Score: 1

    So 31 April?

  36. Today... 3-14-15... by iq145 · · Score: 1

    ...but it goes further, at 9:26am

  37. Re: 14/3/2015 is no more logical by billstewart · · Score: 1

    yyyy/mm/dd has the advantage that it sorts correctly. dd/mm doesn't, especially if you drop leading zeros.

    --

    Bill Stewart
    New Fast-Compression-only CPR http://preview.tinyurl.com/dy575ks
  38. Friends of a friend got married yesterday by billstewart · · Score: 1

    They were both geeks, picked Pi Day as a day to get married. (I doubt they were the ones mentioned in the article, but I don't know them.)

    Friends of mine had a Pi Day brunch yesterday. It didn't start at 9:26am, because that was just way too early, so they decided to end it at 9:26pm if anybody was still there. We reset one of the clocks to Eastern time so we could do 9:26pm EDT, cheer, etc.

    --

    Bill Stewart
    New Fast-Compression-only CPR http://preview.tinyurl.com/dy575ks
  39. Hope you've all survived the Ides of March by billstewart · · Score: 1

    The Roman calendar was really a hopeless mess of leftover lunarcy. Some months the Ides are the 15th, most the 13th, kalends were the first, and you counted dates forward to the next ides, kalends, or nones.

    --

    Bill Stewart
    New Fast-Compression-only CPR http://preview.tinyurl.com/dy575ks
  40. No, it's Don Mclean day by Doghouse13 · · Score: 1

    ('cos it's American Pi...)