To subscribe, click here.
To submit a letter to the editor, click here.
To pitch a 'My Turn' guest column, email jdalessio@news-gazette.com.
The number conventionally represented by the Greek letter pi is truly marvelous.
It can be defined as the ratio of a circle's circumference to its diameter, but pi pops up all over, not only in the geometry of circles. What is the sum of the inverses of all squared positive integers? Remarkably, 1 + 1/4 + 1/9 + 1/16 + 1/25 + ... = (pi x pi)/6.
Equally astonishingly, pi = 20 arctan(1/7) + 8 arctan(3/79). Pi is everywhere, and merits celebration.
March 14 has been commemorated as "Pi Day" at least since 1988, when the San Francisco Exploratorium hosted an event in honor of this transcendental number. (A transcendental number cannot be expressed as the root of a polynomial with rational coefficients. There are infinitely many of them, but proving that a given number is transcendental can be very hard.) The inspiration is obvious: 3.14 are the first three digits of pi.
But hold on. When did you last see a date written with periods separating the day and month, in that order? Except when discussing Pi Day, Americans almost never employ periods to separate the day, month and year in a date. The slash (southwest to northeast) is the most popular separator in the U.S., with a dash or minus sign trailing behind as a second option. Of course, neither 3/14 nor 3-14(= -11) is at all a good approximation of pi.
A helpful Wikipedia page reviews the most common date formats by country worldwide. The closest thing to an official norm is the formal international standard of YYYY-MM-DD (ISO 8601). That ordering makes sense, as it moves downward in unit size, years being larger than months, which are larger than days.
But there is no Pi Day in sight with the "MM-DD" format, given the resemblance to subtraction. Using periods to separate numerical representations of day and month is not uncommon, but it happens exclusively in countries that use DD.MM, and there is, of course, no 14th month. Scour the details on that page and you find, sadly, that nowhere in the world is the "MM.DD" format that renders March 14 as 3.14 normal.
Is Pi Day thus impossible? Fortunately, July 22 is an alternative "Pi Day" because 22/7 is actually a slightly better approximation of 3.14159265... than is 3.14. July 22 is sometimes referred to as "Pi Approximation Day," a designation that should annoy anyone who holds pi in affection, given that both 3.14 and 22/7 are approximations of the real number, which cannot be written down in full (as suggested by the trailing periods above).
Where in the world is July 22 written as 22/7? The smallest-to-largest ordering of day then month then year is quite common, and at least some of the nations where that is the preferred ordering employ slashes instead of periods or dashes.
There are about 40 instances of the DD/MM format being identified as in use, albeit very often as a less-popular alternative to DD.MM or DD-MM. Cyprus, Iraq, Italy, Niue, Palestine, Saudi Arabia, Somalia and Thailand are the only territories where that format is uniquely identified as the local norm. Wikipedia is never wrong, right?
I started perusing government websites for each of these polities, to see if I could confirm the date formats. Discouragingly, the English version of the Italian Chicago consulate's news page permits searching by dates with MM/DD format, not DD/MM. Most of the dates at the English-language version of the government of Niue's website are written with months rendered as words, not numbers. Reassuringly, however, legislation dates employ DD/MM/YYYY. Maybe it is better not to check on the Wikipedia wisdom too carefully in this instance.
So, this coming July 22, consider heading to Niue in the South Pacific for a slice of papaya-coconut cream pie, and to think fond thoughts about pi. Do the same at home on Friday if you like, but know that, alas, it isn't really Pi Day here in the U.S., or anywhere else.