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Pi Day (wikipedia.org)
67 points by brudgers on March 14, 2015 | hide | past | favorite | 30 comments

DO seems to have some fun today as well :) https://twitter.com/digitalocean/status/576739557854425088

In Significant Coincidences For Pi Day:

Get the 0-9 Dial Mitutoyo caliper:

The height of an HP 10c, 11c, 12c, 15c etc shirt pocket RPN calculator is 3.1415 inches.

Get that HP calculator to verify last night's dream:

There are 3.14 inches in 2^3 cm's.

And if you want to celebrate e day and pi day on the second of July, 2018, know:

(pi^5+pi^4)^(1/(3+2+1)) = 2.7182818


e^(3 x 2)/(pi^(2 x 2)+pi^(2 + 1)) = 3.141592

simplifies to:

e^(3 x 2)/pi^(2 x 2)-e^(2 x pi x i) = 3.141592


I usually try to do something fun for the pi searcher for Pi day. (http://www.angio.net/pi ). But this year, I felt lazy, so I abused the RESTful interface I created last year to find the first occurrence of "piday" in Pi, using a very simple alphanumeric mapping (00 == a, 01 == 1, 25 == z, 26 == a, etc.).

The answer is to search for: 1560810050 and check the alpha display below the results. :)

But the method is the part I shouldn't encourage others to use... but, hey, it's Pi day, what's a few more AWS instances up and running? I was too lazy to do this the right way, so I pounded on my own web interface with a quick little python script. Please don't judge me for poor python written quickly the morning of pi day. ;-)

  import urllib2
  import json
  import time
  for p in xrange(15, 100, 26):
    for i in xrange(8, 100, 26):
      for d in xrange(3, 100, 26):
        for a in xrange(0, 100, 26):
          for y in xrange(24, 100, 26):
            pistr = '{:=02}{:=02}{:=02}{:=02}{:=02}'.format(p, i, d, a, y)
            r = urllib2.urlopen("http://www.angio.net/newpi/piquery?q=" + pistr).read()
            dat = json.loads(r)
            idat = dat['results'][0]
            if idat['status'] != 'notfound':
              print dat

(Ahem - I should point out for others that I open sourced the pi searcher code a year or so ago, so if you really want to pound on it, you can do it locally, in go -- https://github.com/dave-andersen/pisearch )

Where is `{:=02}` documented? I've never seen this before and it's pretty awesome.

I just had the odd experience of having a small apple pie delivered to me as part of an uber promo where they are driving around Brooklyn with a car full of pies and delivering them to people.

So there's that.

I built this thing to send a Pi day tweet at the exact right moment (US 12-hour format, your local time PM).


> America (read: USA) is the only country that uses the month-first date system

Unfortunately April only has 30 days.

I think the main problem is that we only have 12 months a year.

Pi approximation day 22/7 works for these parts of the world.

Isn't month first better? It is easier to sort MMDD than DDMM.

That doesn't matter quite as much, mainly the inconsistent month/day/year system is quite confusing. Note that the ISO time standard does use YYYY-MM-DD.

ISO is big endian, conventional rest-of-world is little endian, and the USA is mid endian.

That really doesn't seem easier at all...

Especially when it's MMDDYYYY ;]

ISO 8601[1] to the rescue!

[1]: http://en.wikipedia.org/wiki/ISO_8601

Also, happy birthday to Albert Einstein and me (in that order of significance).

You only need 39 digits of pi to measure the circumference of the observable universe within the width of one hydrogen atom.

Once you memorize them, you can proudly wear this t-shirt:


SOURCE! please.

Seems like a good time to post 355/113 http://davidbau.com/archives/2010/03/14/the_mystery_of_35511...

One of the best easy to remember approximations of Pi

Did a parkrun event (www.parkrun.org.uk) this morning and they had pace runners there this week with target times printed on their back. One of them had pi printed on his shirt and it wasn't obvious what his actual target time was. The run begins at 9am. It was only later that we realised he was _probably_ setting pace for 26 minutes (i.e. to end at 9.26am).

Pah, I celebrate Pi Time every day, at 3.14. And 15 seconds. And 926 milliseconds. And ...

At Petsi Pies[1] in Cambridge, MA if you can recite 314 digits of pi you get a free large pie (the contest started at 9:26AM)

[1] http://petsipies.com

In case you ever need it, here is Pi to a million decimals. http://www.pimillion.com

1337% of Pi is 42.

Also, don't forget Tau Day on June 28th!


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