Slashdot Mirror


Pi Day and an Interview With a Pi Researcher

JoshuaInNippon writes "In honor of Pi Day, March 14 (or 3.14 for those who may need a hint), readers may be interested in reading an interview with Professor Daisuke Takahashi, the Japanese researcher who found 2.5 trillion digits of Pi back in August, before being apparently being edged out in December by a French computer programmer looking to prove his efficient coding abilities. Professor Takahashi's interview gives some unique insight into one man who truly marvels at the number that has driven people to ever greater lengths to find more digits for centuries." Plant Kingdom adds "There have been a number of proposals for alternatives to March 14 (see the Wikipedia page for Pi Day). Here's mine: when the Earth has gone through 1/pi-th of its orbit, as measured from Winter Solstice to Winter Solstice. I've put together a web site to make the case."

34 of 188 comments (clear)

  1. I don't get it by Hognoxious · · Score: 5, Informative

    Huh? Pi isn't 14.3 or 14/3.

    --
    Confucius say, "Find worm in apple - bad. Find half a worm - worse."
    1. Re:I don't get it by isorox · · Score: 2, Informative

      Huh? Pi isn't 14.3 or 14/3.

      No, but it's close to 22nd July.

    2. Re:I don't get it by mrsquid0 · · Score: 5, Insightful

      No, day-month-year is more sensible since the size of the unit is increasing monotonically. The sanest way to do it would be year-month-day, because then you could increase the precision of the time string to whatever you needed just by adding units to the right. The month-day-year system is probably the lease sensible method of the lot.

      --
      Just because you are paranoid does not mean that no-one is out to get you.
    3. Re:I don't get it by MobileTatsu-NJG · · Score: 3, Interesting

      The month-day-year system is probably the lease sensible method of the lot.

      Not to those of us who often work with dates that often land on the next month. As a friend of mine likes to say "six of one, half dozen of the other."

      The sanest way to do it would be year-month-day...

      This gets my vote.

      --

      "I like to lick butts!" by MobileTatsu-NJG (#32700246) (Score:5, Informative)

    4. Re:I don't get it by Cimexus · · Score: 3, Interesting

      Yup, yyyy-mm-dd is the ISO standard date format for a reason. You get the advantage of easier chronological sorting (ala the US system of month/day), and the unambiguity of the unit size constantly going in one direct (in this case, largest to smallest).

    5. Re:I don't get it by M.+Baranczak · · Score: 2, Funny

      In Indiana, it's celebrated on March 2.

    6. Re:I don't get it by isorox · · Score: 2, Funny

      It's also nearly my birthday, so another reason to celebrate. :-)

      Surely you mean approximately your birthday?

  2. Pi day? by burris · · Score: 4, Insightful

    Judging by the big hunk of meat in my 'fridge, today is Steak and BJ Day. Pi day just isn't nearly as fun.

    1. Re:Pi day? by zippthorne · · Score: 3, Funny

      Pi day is irrational, but at least it's real.

      --
      Can you be Even More Awesome?!
    2. Re:Pi day? by interkin3tic · · Score: 2, Funny

      Judging by the big hunk of meat in my 'fridge, today is Steak and BJ Day

      Please tell me the "big hunk of meat" in your fridge is for the steak part of that day. You're doing it wrong if not.

  3. Don't forget. by myocardialinfarction · · Score: 4, Funny

    Don't forget it's also mother's day. And nobody makes better pi than mom. /duck

  4. US-centricity by garyok · · Score: 5, Funny

    In the UK, we have to wait until the 31st April to have pi day. We'll be waiting a while...

    --
    One of the penalties for refusing to participate in politics is that you end up being governed by your inferiors - Plato
    1. Re:US-centricity by sakdoctor · · Score: 2, Informative

      TFA suggests Archimedes' approximation of 22/7

    2. Re:US-centricity by keeboo · · Score: 2, Funny

      I'm programming at this moment and it was just what I needed! Thanks!

      #define PI_VALUE 22/7

    3. Re:US-centricity by mrsurb · · Score: 4, Funny
      Don't forget to localise for differing values of pi:

      #ifdef INDIANA
      #define PI_VALUE 3
      #endif

  5. Stupid by Anonymous Coward · · Score: 4, Insightful

    This is stupid, who thought MONTH - DAY - YEAR is a reasonable date format? Do you frequently find yourself asking "Hmm, I wonder what month it is?" And always make people look in the center to find out the date? WTF

    It's like throwing away metric and using some crazy-ass divisible by 12 unit.

    1. Re:Stupid by MobileTatsu-NJG · · Score: 2, Insightful

      This is stupid, who thought MONTH - DAY - YEAR is a reasonable date format?

      The person that noticed that we generally say "March 14th, 2010", so it's more intuitive.

      It's like throwing away metric and using some crazy-ass divisible by 12 unit.

      Oh please, it isn't done right where you are, either. It should be 2010-03-14 so it sorts chronologically and intuitively can't get the month or day mixed up. Your preference is simply different, not less stupid. This isn't one of those topics you can use to pose as one of the smarter people.

      --

      "I like to lick butts!" by MobileTatsu-NJG (#32700246) (Score:5, Informative)

    2. Re:Stupid by Cimexus · · Score: 3, Informative

      Bad form replying to one's self but this is interesting: http://en.wikipedia.org/wiki/File:Date.png

      The number of countries using the US system is pretty small. It's basically the US and a few random places like Palau and Micronesia.

      But - there are quite a few variations on date format, more than I thought :)

    3. Re:Stupid by GospelHead821 · · Score: 2, Funny

      Base 12 is an excellent base. Metric/decimal is okay but we're not monkeys anymore. Can't we please get over the fact that we have just 10 fingers? Base 12 makes it a lot easier to work with common fractions. Halves, quarters, AND thirds are all easy to calculate. Assuming you accept that the inch is no more or less arbitrary than the centimetre as a unit of measure, then in base 12, feet and yards become completely sensible. A great gross of yards (12^3 = 1728 yards = 5184 feet) is pretty close to today's arbitrary mile. 12-hour days make a lot more sense too. If I remember correctly (and I might not; I welcome corrections if this is wrong), we do it that way in the first place because our timekeeping system evolved from Babylonian timekeeping and the Babylonians used a base-12 number system.

      Of course, in base 12, pi is no longer 3.14159. It approximates to 3.18480. I wouldn't mind selecting a definition of pi day that frees us both from the Gregorian calendar AND from our monkey-finger numeric base.

      --
      Virtue finds and chooses the mean.
      Aristotle, Ethica Nichomachea
  6. Re:My suggestion by jschen · · Score: 3, Funny

    Regarding 2.7182's statement: I'm surprised you're not advocating e day (Feb 7? July 2?) instead. The combination would be good, though. Celebrate pi and e, and we get pie! How about pi + e day? At ~5.9, that would make May 9 or Sept 5 into Pie Day.

  7. a French computer programmer? by short · · Score: 2, Interesting

    Calling Fabrice Bellard "a French computer programmer"? Is it a joke?

    1. Re:a French computer programmer? by mukund · · Score: 3, Informative

      OTOH, reading Bellard's FAQ on his latest result does seem like he was interested more in fast algorithms and not in Pi. So I stand corrected. Still.. he's not some random programmer to us. :P Following links from his FAQ, I found two cool books:

      --
      Banu
  8. Re:Ellipse != Circle by Ardeaem · · Score: 3, Informative

    Pi is relevant to the circumference of circles. The earth has an elliptical orbit. http://en.wikipedia.org/wiki/Circumference

    Um...pi is relevant to a lot of things, including ellipses. And besides, the orbit of the Earth has very low eccentricity, meaning it is very close to a circle. Who modded the parent "informative"?

  9. What's the significance of 1/pi? by Saint+Stephen · · Score: 2, Interesting

    1/pi is not pi. It's like celebrating the third time something happened by doing something one third of the way through and then stopping!

    "When a circle's diameter is one unit, then the cirmcumference is pi units." [http://en.wikipedia.org/wiki/Pi]

    So if a year is "one unit", we should celebrate pi every 3.14 years or something.

    1. Re:What's the significance of 1/pi? by LordVader717 · · Score: 2, Informative

      For every pi proportioality the reciprocal relation is a 1/pi proportionality, so it's every bit a significant. For a near-circular Earth orbit 1/pi of a year is the time when the earth has passed the equivalent of the diameter of it's orbit and swept an area the size of of a rectangle made from it's major and minor axis.

  10. RE: yeah, okay by Anarchduke · · Score: 4, Insightful

    Oh Jesus. Really?

    Okay, I'm about to troll, but...

    First, do we really need a holiday for every fucking thing out there? Where the hell is dung beetle day? Aardwolf week? Permian Extinction Day?

    Secondly, you invested enough energy into worrying about WHICH day should be Pi day that you created a website over it?

    Finally, if Pi gets its own day, I think its entirely fair that 1.618 get its own celebration. Phi is easily as fascinating a number as Pi, so why didn't you get your panties in a twist over not having Phi day?

    Sometimes, you CAN be too much of a geek.

    --------------
    End of Troll.

    --
    who prays for Satan? Who in 18 centuries has had the humanity to pray for the 1 sinner that needed it most? ~Mark Twain
  11. Did he find a message? by wisebabo · · Score: 3, Interesting

    I understand that in the book "Contact" by Carl Sagan, when the scientists meets the aliens he asks them a question:

    Scientist: Do you believe in God?

    Aliens: Yes.

    (Astonished) Scientist: Really?! Why?

    Aliens: We have proof.

    Scientist: Proof?!!!

    Alien: Yes, when we decoded Pi to (a very large number) we found a Message...

    Of course this idea was exploited in a different way by the movie "Pi". (Sorry didn't see it either.). In any case, if Pi is truly Random (it is isn't it?) won't every possible message occur? Just like those monkeys with their typewriters (if you don't know what a typewriter is look it up).

    1. Re:Did he find a message? by pcolaman · · Score: 4, Funny

      What the fuck is a monkey?

    2. Re:Did he find a message? by jc42 · · Score: 3, Interesting

      In any case, if Pi is truly Random (it is isn't it?) won't every possible message occur?

      Hmmm ... You must be using an unusual definition of "random", which usually means that the value is unpredictable. Pi is the opposite of random. It's precisely defined and always has the same value for anyone who calculates it correctly. (Which leaves out the religious folks, but that's to be expected for anything requiring validity. ;-) Pi would even be the same in a different universe with different physical laws, because its value isn't dependent on anything physical.

      As for every message occurring, I think you're thinking of normal numbers. There is a conjecture that pi is normal, but it hasn't been proved. So far, statistics of the digits of pi are consistent with it being normal to as many digits as have been tested. A normal number does contain every possible message, in every possible encoding. If pi is normal, then so is e. [The proof is trivial for anyone who knows the well-known equation relating e and pi.]

      And yes, this mathematical (ab)use of the word "normal" is one of the silliest things that mathematicians have ever done. But there is a long tradition of such silly misuse of common words as mathematical terms.

      --
      Those who do study history are doomed to stand helplessly by while everyone else repeats it.
  12. Re:Ellipse != Circle by noisyinstrument · · Score: 3, Funny

    Clearly it was a case of circular logic.

  13. Re:My suggestion by fastest+fascist · · Score: 2, Funny

    Don't you know "e" is illegal in most countries?

  14. Re:Ellipse != Circle by techno-vampire · · Score: 2, Informative
    Who modded the parent "informative"?

    This is Slashdot, in case you hadn't noticed. Only on Slashdot is pointing out the trivially obvious considered "Informative."

    --
    Good, inexpensive web hosting
  15. Re:Efficient coding abilities? by Rockoon · · Score: 2, Informative

    Yes and No.

    If the doubling time of computational power is N hours (a bastardization of Moore's law, approximately 17500 hours.. or two years), then it never makes sense to start a calculation that will take more than 2N hours.

    For easy visualization of this concept, lets suppose you have a program that will take 6 years to complete if run on todays fastest hardware, and you begin it March 14th, 2010 .. It is thus scheduled to complete computation on March 14th, 2016.

    But you have an adversary who wants to beat you to the punch and announce the programs output before you do. He can wait until March 14th, 2012, exactly two years later than your start date, and at that time buy the fastest hardware of that time period. On March 14th, 2014 his program will overtake yours, and it will finish on March 14th, 2015.

    He beat you by 1 year even though he started 2 years later than you did. As you see, it is a futile waste to perform such very long calculations as long as moore's law holds.

    A similar concept was introduced to me in a space-ship through experiment. Humanity builds its first set of inter-galactic space ships which can achieve 50% the speed of light, and these ships set off to explore the universe. Surprisingly those first explorers all arive at stars populated by human beings, humans who themselves set off exploring AFTER they did, because inter-galactic drives improved to 98% the speed of light after only a few more years of development.

    --
    "His name was James Damore."
  16. You just got pwnd by Captain Literal. by Hognoxious · · Score: 2, Funny

    I've got 0 through 9 here on my keyboard, I'd have thought with a trivial bit of rearrangement they'd just about do it.

    --
    Confucius say, "Find worm in apple - bad. Find half a worm - worse."