
PI to 2.7 trillion places on a desktop - teeja
http://bellard.org/pi/pi2700e9/
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bulanga
In case you didn't know, this is the guy who started ffmpeg which does the
heavy lifting in projects like VLC, etc.

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Smirlouf
He's also behind QEMU (cross-platform, multi-architecture CPU emulator/dynamic
recompiler/virtualizer), TCC (the Tiny C Compiler) and various other projects.

see <http://bellard.org/>

~~~
lsc
QEMU also provides components used by Xen HVM mode and the KVM virtualization
systems.

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niyazpk
Apart from the interestingness angle, can somebody explain to me how the value
of π to 2.7 trillion decimal places is useful?

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RiderOfGiraffes
Just a few off the top of my head ...

It's still not known if pi is "normal" - has an equal distribution of digits.
This can be used to test the hypothesis.

The digits of pi are apparently random, so different calculations on different
machines can be compared to see if either is behaving oddly.

Computing pi is sometimes used as a benchmark for a machine's speed.

Some people are unreasonably obsessed.

The digits of pi can be used as "concrete random" numbers.

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paraschopra
>The digits of pi are apparently random, so different calculations on
different machines can be compared to see if either is behaving oddly.

Can you please explain what do you mean by this? Digits of pi must be same no
matter which machine is used to calculate.

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RiderOfGiraffes
Your use of the word "must" is the key. The digits of pi are _supposed_ to be
the same, but if a cosmic ray flip a bit, or if the machine becomes unstable
because it runs hot, or if there's a bug in the FPU (such as happened to
Intel) then results can differ, even when they shouldn't. Computing pi to very
large numbers of digits is a standard warmup to make sure that new hardware is
working correctly. It's only one of many tests, but it has found hardware
bugs.

I remember using a machine that started to give incorrect answers when it ran
too hot, and it ran hot when it was working full speed. We had to tweak the
compiler to add extra NOPs into the instruction path becuase the micro-code
used less power in a NOP, thus generated less heat.

EDIT: I've realised this is another example of the sofware fixed the hardware:
<http://news.ycombinator.com/item?id=1031384>

