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Blue Gene/P Reaches Sixty-Trillionth of Pi Squared
Reader Dr.Who notes that an Australian research team using IBM's Blue Gene/P supercomputer has calculated the sixty-trillionth binary digit of Pi-squared, a task which took several months of processing. Snipping from the article, the Dr. writes: "'A value of Pi to 40 digits would be more than enough to compute the circumference of the Milky Way galaxy to an error less than the size of a proton.' The article goes on to cite use of computationally complex algorithms to detect errors in computer hardware. The article references a blog which has more background. Disclaimers: I attended graduate school at U.C. Berkeley. I am presently employed by a software company that sells an infrastructure product named PI."
From the blurb:
Oh, I expected the sentence to end with, "...and I still don't know why the fuck anyone cares about a number this long."
I'm going to the bar. Who's with me?
Phew. I was afraid they weren't going to discover that before the end of april.
What does that number "do"?
Pi is famous, and the more well known number to crunch. Why crunch Pi Squared? Can't you just square Pi?
My first Journal Entry ever, in 8 years! http://slashdot.org/journal/365947/aphelion-scifi-fantasy-horror-poetry-webzine
http://www.toothpastefordinner.com/031208/how-many-digits-of-pi-do-you-know.gif
So they just calculated that one binary digit?
Was it a 0 or an 1?
The Tao of math: The numbers you can count are not the real numbers.
Is there the equivalent to pi in three dimensions? I mean, the ratio of a sphere's surface area to the area of the circular plane bisecting it? Maybe it has no significance.
"Disclaimers: I attended graduate school at U.C. Berkeley. I am presently employed by a software company that sells an infrastructure product named PI.""
That's *not* a DISCLAIMER. That's a DISCLOSURE.
Not PI squared, who would ever want more than fifteen digits of that? But the square root of PI... that is where we require 18 trillion decimal digits.
...neither TFA nor TFBlog tell you which it is. So...flip a coin.
The only surefire protection against Microsoft infections is abstinence. - The Onion
Yes really, why squared? I prefer mine round. Atm I feel like pumpkin would be best.
Well within it, actually.
1.67E-13 is FAR larger than 2^-6E13. Stupid math.
The only surefire protection against Microsoft infections is abstinence. - The Onion
Why not compute digits of e? What's all this obsession with pi? For me, this time it's personal.
Disclaimer: I go to Berkeley so I am better than you.
hm'k?
we know the world is flat and all...
don't let them mad scientists get to ya!
cheers.
Or really, even on earth. Ever hear about special (or general) relativity and the fact that matter-energy warps spacetime? Pi is only correct in flat space -- devoid of matter or energy, which the galaxy isn't, nor is earth - some folks heads might qualify.... There is no flat space anywhere we know of, and if you put the gear into it to measure pi there, it wouldn't be flat anymore. Doh! The stuff copy-writers come up with to spice it up for 'tards shows what retards they are themselves.
Why guess when you can know? Measure!
... enough to compute the circumference of the Milky Way galaxy to an error less than the size of a proton
Why bother carrying out the computation to such precision when the error in your measurement of the radius (or diameter) would be so much bigger.
Life's a tale told by an idiot, full of sound and fury, signifying nothing.
Not square.
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)
Wow. You figured that out yourself. You are a freaking genius of the highest order. Please carry my babies do they might be as smart as you someday.
No shit, sherlock. The whole point is to give an idea of the meaning of 60 trillion digits. If 40 is more than enough for any imaginable purpose, then 60 trillion is completely ridiculous. No one was suggesting you'd use pi to measure the diameter of a galaxy.
if you were really smart, which you aren't, you would realize that
1) The galaxy is not circular
2) The meaning of "galaxy" is quite ambiguous and it certainly does have a clearly defined border... much like our atmosphere
3) That your mom should have aborted you.
By the Indiana legislature; it's 9.0.
That is phenomenally useful.
There is no point to this. Pi is an irrational number you can't digitize. Just continues to promote the ignorance of the nature of Pi.
Wow, a BlueGene/P is being used to run something other than Linpack. That's gotta be a first.
Disclaimer: I didn't attend graduate school at U.C. Berkeley, nor am I presently employed by a software company that sells an infrastructure product named PI. I have, however, wasted way too much time trying to get codes to build and run (slowly!) on BG/* platforms.
It's plain easy to calculate the sixty-trillionth digit of Pi... as long as you don't care about the digits that come before it: http://www.sciencenews.org/sn_arc98/2_28_98/mathland.htm.
Buy Text Processing in Python
I know the last digt of pi! It's zero... in base pi.
HSJ$$*&#^!#+++ATH0
NO CARRIER
Only kind of. Ever hear about the Gauss Bonnet theorem? In a curved space, the value of Pi still matters.
http://www.bash.org/?696997
what is the volume of a pizza of radius z and thickness a ?
answer: pi z z a
You humans and your base-10 arithmetic. I use base-pi arithmetic. So pi = 1, and pi squared = 1. Computed in a nanosecond. Of course, it makes other computations slightly more complex. For example, I have about 3.183095825842514 fingers, more or less...
Give me 10 attempts and I guarantee I can guess this digit faster than the computer can compute it.
Of course, this being slashdot, I didn't RTFA.
Question: Knowing the diameter of the observable universe, how many digits of Pi are needed to calculate the circumference of the observable universe, accurate to within 1 plank length?
Answer: 62 digits. Here they are: 3.14159265358979323846264338327950288419716939937510582097494459
Calculated this one myself.
Yeah, because it's so hard to calculate 2*pi given pi (to how ever ma).y decimal places.
I think it would be tremendously funny to find out, at some suitably ridiculous decimal place, that all subsequent places are zero repeating. It would utterly break some people's heads to find out that the number is only "very, very particular," rather than "irrational."
It is the one hope that holds my interest when I read about crunching these numbers.
Pi = 3
If anyone remembers Sagan's novel Contact (quote from wikipedia):
YTMND inspired a lot of people to learn more digits of Pi. "Pi" by Hard n Phirm became a minor fad there.
There is a sequence of several 9's fairly early in the decimal expansion of pi though. People have joked about memorizing pi out to 770 digits so they can say "...999999 and so on."
But seriously, the irrationality of arctan(1) (which equals tau/8 or pi/4) has been proven.
I mean are they expecting some kind of repeating value or pattern? Wouldn't the computational time be better spent determining when the Leafs will win a Stanley Cup?
The most relevant part of that article was:
"Isaac Newton computed Pi to at least 15 digits, in the plague year 1666, although he sheepishly acknowledged “I am ashamed to tell you how many figures I carried these computations, having no other business at the time.”".
'A value of Pi to 40 digits would be more than enough to compute the circumference of the Milky Way galaxy to an error less than the size of a proton.'
I freaking love mathematicians. Everything has a proof when you can't actually prove it, coming or going.
Everyone knows PI squared is ten.
What IS the sixty trillionth digit of Pi? That's what I'd like to know.
Wasn't that value set in the bible long before?
The Tao of math: The numbers you can count are not the real numbers.
The algorithm used to do this sounds like it may be this one: BBP Formula.
This is also the same algorithm used in the browser based Distributed Pi project.
The only difference between using the BBP formula to generate Pi or Pi^2 is the use of different constants.
1. Starting at the 60 trillionth binary decimal place, pi^2 is, in base 8, 601145053032. Expanding to base 2 this is 110 000 001 001 100 101 000 101 011 000 011 010. You can see more at this post on a blog run by David Bailey and Jonathan Borwein of BBP-type formula fame.
this always comes to mind when hearing about someone computing the $BIGth digit of $CONST
ultra short summary: the fuckwit whose photo appears in TFA has no claim whatsoever to the algorithm actually used to compute distant digits of various constants
It's good to know these computer scientists and mathematicians are not wasting computer funding on a worthless project.
The purpose of existence is to make money.
Disclaimer: I like to eat pie
A small region of space is sufficiently flat for practical use, in the same manner that a flat map can be used to show a small region of the surface of the earth with low enough error to permit navigation.
The bible value is three exactly. It's actually detailing the exact size of a ceremonial container: Circular, ten cubits across, thirty around (Big). The 0.1 discrepency is simply because they didn't measure very precisely at the time, and rounded as convenient. It still bothers a few people who have trouble accepting that something made to the design of God could be so sloppily and imperfectly built, so there are a few religious traditions that explain it as esoteric code. Most just accept it as rounding error.
There is no error at all, those are the correct number of whole cubits. You'd have the same issues if the measurement were given to a 0.001 of a cubit. Those who claim some error are ignorant of the concepts both of accuracy and precision.
But the Goodyear Dealer still won't believe me when I show them my tire is out of round.- Go figure
"Computers are a lot like Air Conditioners" "They both work great until you start opening Windows"
Surprised EVERYONE.
To a physicist, pi is somewhere around a million, give or take a few orders of magnitude. That's close enough FAPP, anyway.
Since her/his company does not actually manufacture pi, nor does s/h/it have any financial interest in the n-trillionth digits of it. So in fact it was a gratuitous mention of the employer for no reason other than the (admittedly pretty plausible) inference that lots of us would rush off to google and try and figure out who he was referring to.
In other words, it was nothing but an advertisement; a free plug, sanctimoniously and hypocritically posing as a disclosure of interest. It left a bad taste in my mouth.
because we can :)
Free speech was meant to be free for all... how can anyone grow up in a nanny state ?