Tag Archives: pi day

PI DAY 2018!

Happy pi day!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

Pi Day as a holiday is 30 years old this year (unless someone had been celebrating quietly on 3/14’s before Larry Shaw publicly founded Pi Day at the San Francisco Exploratorium in 1988)!

While last year was a pi day snow day for us, this year the snow has mostly missed us in Maryland, while Boston area folks have had several huge storms in a row, and some of them do have a pi day snow day today!

The day was off to a good start this morning with a beautiful pi day sunrise:

I was up early to buy some pies, as per usual, when I stumbled across a pi-day pie sale! While I’ve seen photos of these before on social media, this is the first time I’ve actually come across one in person on a pi day myself!


I made my chalkboard a little busier than usual, including a few extra pi facts:

I also wore a new pi tie today (some years I’ve worn pi t-shirts). You can’t tell from the photo, but the image/pattern is made up of pi’s digits!

My first period AP CS A (Java / object-oriented programming class, with juniors and seniors) is the only class I did a pi-focused lesson with this year. In my other classes, we took a ten-minute pi and pie break, and talked about pi facts while eating, then back to our regularly-scheduled lesson. But in AP CS A, we coded an infinite series for pi in Java. We used the Leibniz formula, relatively easy to understand and code: 1/1 – 1/3 + 1/5 – 1/7 + 1/9 – 1/11 + 1/13 – …

This actually converges fairly slowly, compared to other infinite series for pi. Here are the results after ten terms, with the terms included on the left, and the running summation on the right of each line:

Here we are after 1000 iterations, just the sums:

And after a million terms, we’re getting pi accurate to five digits:

A million terms took a few minutes to run, so we didn’t dare try ten million, for fear we would break our ancient computers! Nor did we try to break the record of 22 trillion digits of pi, which would need many many times more terms if we were to use this series 🙂

Also today, in other news, a nationwide walkout against gun violence, which students at my school participated in as well. And I took two students on a field trip; the students had built a custom-engineered bicycle for a kid with a disability last month during National Engineering Week, and today we got to deliver the bike to the kid and his mother. So that was pretty cool.

Anyway, that’s how my day went, hope your pi day was similarly awesome!

Here’s my round-up of a few Pi Links:

And a few really creative pi-related photos, found via Twitter (linked to their sources):


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Pi Day Snow Day!

After a winter with no snow (no snow that’s stuck, anyway, there’ve been flakes in the air a few times), it’s a pi day miracle: a snow day!

Last night, when the call was made, we were predicted to get 6-12″, but with more sleet than snow, we’re on the low end of that range or a bit less. Here’s a joke I’m stealing from my friend Matt:

In honor of pi day, and with the extra free time of a snow day, I baked a quiche pi!


I tried to arrange the broccoli in the shape of the symbol π (pi), which you can see if you look closely 🙂 I’ve outlined it below.


And, of course, I had to break out my pi cutter to slice it with!


If you’re more ambitious than I am with your pi day baking needs, you could  try a “celebrity chef” pie, or Vi Hart’s Venn Pi-agram (she has both a dessert pie and a pizza pie version):

In Pi Day news, there have now been over 22 trillion digits of pi calculated! Hooray!

Whether or not you, too, are snowed in, have a wonderful pi day, and check out some of the following links!

Even though there are skeptics out there,

I agree with Cookie Monster:

Me love pi (and pie)!

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Happy (Round-Up) Pi Day!

Greetings once again, one and all!


Pi Pies (photo by djwtwo on Flickr)

It is PI DAY, y’all – gather round and roll out the red carpet for that most glorious of numbers,


a.k.a π,

a.k.a pi.


In fact, though we made a big deal of last year’s celebration as the “Ultimate Pi Day”, or the “Pi Day of the Century”, a case can be made that today is even more special! Today’s date, 3/14/16, is a rounded-up version of pi to four decimal places (rather than a truncated version like last year); it also only comes around only once a century; and in fact 3.1416 is about nine times closer to the actual value of pi than 3.1415 is! 😉

If you’re a little bummed out that we won’t have a “pi day of the century” next year (after all, 3.1417 doesn’t seem too special), check out this article (via MAA) which proves that, for some norm other than the Euclidean distance, there is a “pi” for that norm that will match that year–thus every pi day can be the “pi day of the century”!

I wore a shirt with a similar message today! (Image via Cliff Pickover)

I wore a shirt with a similar message today! (Image via Cliff Pickover)

OK, here’s your round-up of cool pi links:

Apple Pi (Image by elips, via Cliff Pickover)

Apple Pi (Image by elips, via Cliff Pickover)

HAPPY PI DAY !!!!!!!!!!!!!!!!!!!!!!/!!!!!!!

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Happy Pi Day everyone!

This year is extra special, since it’s 3/14/15! Some have called it the “Ultimate Pi Day”, or the “Pi Day of a Lifetime” or the “PiPocalypse” (although I may be mixing that last one up with the snowstorm of a few years ago).

I wish you all an extra-wonderful ten-digits-of-pi-moment at fifty-three and a half seconds past the twenty-sixth minute of the nine o’clock hour this evening, or 3/14/15 9:26:53.5.

On this pi day, I encourage you to celebrate pi, and math, and the amazing things you can do with both! From last year, here are:


1. Share pi (and pie) with friends
2. Read and learn more about pi
3. Contemplate the wonder of the universe and mathematics’ role within it
.14159…. Shout “Happy Pi Day!” and/or “Happy Pi Moment” at the top of your lungs when the appropriate time occurs

Some awesome pi-related things to check out this year:

  • A cool pi day sudoku
  • How to estimate pi by weighing a circle [video]
  • “Why Pi Matters” by Stephen Strogatz
  • This argument of pi vs. the Pythagorean Theorem
  • An article on this pi day by Borwein & Bailey, famous pi mathematicians
  • This video making fun of our obsession with pi, tau, e, golden ratio, and other *amazing* numbers – it might take a little math knowledge to get the joke but it’s hilarious once you do

Hope you have a great pi day, and many more!

– Nick the Pi Guy


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Pi and Pancakes

Happy Pi Day – 1 everyone! Only one more day until the pi day of the century!


In the meantime, check out this awesome pancake 3D printer (article, kickstarter).

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Roots of Unity Final Projects


These are the results created last November for the art/math integration project described here.


By the way, happy pi week everyone!

Pi Week

Pi Week

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Pi Day 2014

Once again, Pi Day has arrived!

As you probably know, pi (π) is a mathematical constant found in circles and throughout mathematics! Since pi’s decimal expansion starts off 3.14…, and today’s date is 3/14, we celebrate pi and all things mathematical on this day!

3.141592653589793238462643383279..., to be a bit more precise! Image copyright David Reimannn, found here

3.141592653589793238462643383279…, to be a bit more precise! Image copyright David Reimannn, found here

My Top Pi Ways to Celebrate Pi Day

1. Share pi (and pie) with friends
2. Read and learn more about pi
3. Contemplate the wonder of the universe and mathematics’ role within it
.14159…. Shout “Happy Pi Day!” and/or “Happy Pi Moment” at the top of your lungs when the appropriate time occurs

Art from pi's digits, copyright Martin Krzywinski

Art from pi’s digits, copyright Martin Krzywinski

Pieces of Pi

Related to #1 and #2 above, here are a few cool tidbits about pi and pi day:

Pi Past

I cannot believe it’s been 10 years since my first pi day expansive email that set up (or continued) a crazy propaganda war between the mathematical constants pi and e. (Going back even further, by my count I’ve been celebrating pi day in some form or another for almost 18 years now!) Just about each year since 2004 I have sent out my annual missive on Pi Day, by email and/or by blog (a few years when March was especially busy for me, I sent out messages on other pi-related days). A list can be found in yesterday’s pre-pi-day post here.

Have a great Pi Day today, and many more!



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