Slashdot Mirror
Nicholas Sze of Yahoo Finds Two-Quadrillionth Digit of Pi
gregg writes "A researcher has calculated the 2,000,000,000,000,000th digit of pi — and a few digits either side of it. Nicholas Sze, of technology firm Yahoo, determined that the digit — when expressed in binary — is 0."
Well, the 243,000,500,000,000,000,002th digit of pi is "4".
Go on, prove me wrong.
*facepalm* So that's 9 in decimal, right?
No folly is more costly than the folly of intolerant idealism. - Winston Churchill
...move along people, nothing to see here.
Good to know they're putting those idle datacenters to good use. It's not like Yahoo has any real users anymore to generate load.
I think it would be neater to be done in binary. Or perhaps convert it to ASCII to see if pi actually represents a story of some kind that is being told to us by the aliens.
"To prevent this day from getting any worse, I'll just read ERROR as GOOD THING" 1GJU8xLuDKDxEs4KLf8fAGyptoDsqvEsBT
"Interestingly, by some algebraic manipulations, (our) formula can compute pi with some bits skipped; in other words, it allows computing specific bits of pi," Mr Sze explained to BBC News.
So why don't they just use their formula to compute the last digit of Pi already?
That would be the rational approach. Who cares about the two quadrillionth digit??
We only know how to calculate it in binary (or any base that is a power of 2). You can't convert to decimal without know all the rest of the digits.
Geez, even I could have gotten it right half the time.
Word. This discovery is useless. Now, if he'd managed to prove that the digit, when expressed in binary, is 2... That'd be something to shout about!
the digit — when expressed in binary — is 0.
Jeez, what are the odds of that?
The interesting thing about this article is how they calculated the digits. They broke the problem up into small pieces and had them calculated in parallel. This approach isn't something that's new or all the unique, but what is is applied to is. Most mathematical calculations are done in a near linear fashion, not in parallel. So for them to be able to do this is a big step forward in how we approach these types of problem in the future.
Of course I'm very interested in this since it seems I'll be doing something like it in the near future as part of getting my master's degree.
It is, but it's encoded in UTF-35, not ASCII.
I've always wondered about these ridiculously precise values of pi - doesn't that imply a measurement (of circumference or diameter) smaller than the Planck length? What's the point of 2 trillion decimals of precision?
No folly is more costly than the folly of intolerant idealism. - Winston Churchill
Bailey–Borwein–Plouffe formula lets you calculate the n-th digit of pi without calculating the n-1 digits.
I wonder what formula was used to calculate the digit here.
We only know how to calculate it in binary (or any base that is a power of 2). You can't convert to decimal without know all the rest of the digits.
Parent is correct, digits of pi can be calculated independently in base 2, 4, 8, 16 or 2^n since the 1990s. So, it is possible to calculate the 2,000,000,000,000,000th number of pi without calculating the digits before that one. Now, if we want to calculate the digit in decimal (or converse the binary digit to decimal), we need to calculate all of the two-quadrillion digits. Knowing this digit is in itself not very interesting.
does this bit from TFA strike anyone else as a bit odd?
"The computation took 23 days on 1,000 of Yahoo's computers, racking up the equivalent of more than 500 years of a single computer's efforts."
So.... 1000 machines, 23 days, assuming embarrassingly parallel that's 23000 days of computation on 1 machine.
23000/365 = 63.0136986 years
now each of those could have 8 cores and they meant 500 years on a single core processor of course.
but still odd phrasing.
And, we know this is correct how ?
Amazing, so is Yahoo's profit projections within five years!
The world's burning. Moped Jesus spotted on I50. Details at 11.
Regardless of what actually happened, there isn't any computation that requires keeping data in memory rather than hard disk. Memory is just faster, if you need more space for the computation, you can always actually use the 100 disks.
"Who is the Journal of Quantum Physics going to believe?" --Stephen Hawking
Well, it will help to date the story to this year, compared to stories that run in 2012 that will say 'defunct technology firm yahoo ...'
"Who is the Journal of Quantum Physics going to believe?" --Stephen Hawking
It's actually 13 orders of magnitude less significant than the 200th.
"Who is the Journal of Quantum Physics going to believe?" --Stephen Hawking
I bet he googled the answer...
dnuof eruc rof aixelsid
It is 1 in binary.
The computation took 23 days on 1,000 of Yahoo's computers, racking up the equivalent of more than 500 years of a single computer's efforts.
And before answering, the computer paused and said, "You're not going to like it ..."
Or perhaps convert it to ASCII to see if pi actually represents a story of some kind that is being told to us by the aliens.
You know that's the revelation at the end of a sci-fi novel by a certain revered astronomer, right?
Say 'gain?
The Admin and the Engineer
You're forgetting all the zombie networks that connect to Yahoo. There's probably a few billion nodes there, and there's not a friggin' chance Yahoo will admit to knowing about them.
It's a small world and it smells funny; I'd buy another if it wasn't for the money; Take back what I paid (SoM)
I can calculate it completely in base pi: 10.0 done. What's all the fuss about? You just need to be smarter when picking your bases and you can avoid all this trouble.
The hexadecimal digit extraction formula for PI (that allows you to skip calculating the previous hex digits) is already known. It can calulcuate the N'th hexadecimaldigit of Pi without calculating most of the previous digits: http://en.wikipedia.org/wiki/Bailey%E2%80%93Borwein%E2%80%93Plouffe_formula
A slower generalized version that can extract the n'th digit of Pi in any base (including decimal) has also been found: http://web.archive.org/web/19990116223856/www.lacim.uqam.ca/plouffe/Simon/articlepi.html
Stylish sheet to fix many problems in Slashdot's D3: https://gist.github.com/801524
The thing that I find funny, is that had they used the Bailey-Borwein-Plouffe formula, they could have saved themselves some very considerable computing resources.
[FUCK BETA]
1.Convert PI to binary
2.Interpret binary PI as ASCII
3.Search for the complete works of William Shakespeare
4.Once found, use number to produce compact William Shakespeare quote generator.