My prior post "inspired me" to generate more digits. Amazing how fast
modern hardware is compared to "super computers" of 20 years ago...
$ time ./pi 25
Version 2.0 of the super_pi for Linux OS
Fortran source program was translated into C program with version 19981204 of
f2c, then generated C source program was optimized manually.
pgcc 3.2-3 with compile option of "-fast -tp px -Mbuiltin
-Minline=size:1000 -Mnoframe -Mnobounds -Mcache_align -Mdalign
-Mnoreentrant" was used for the
compilation.
------ Started super_pi run : Fri Jan 8 18:38:51 CST 2010
Start of PI calculation up to 33554432 decimal digits
End of initialization. Time= 23.996 Sec.
I= 1 L= 0 Time= 76.185 Sec.
I= 2 L= 0 Time= 84.991 Sec.
I= 3 L= 1 Time= 85.697 Sec.
I= 4 L= 2 Time= 84.602 Sec.
I= 5 L= 5 Time= 84.055 Sec.
I= 6 L= 10 Time= 84.457 Sec.
I= 7 L= 21 Time= 83.957 Sec.
I= 8 L= 43 Time= 85.108 Sec.
I= 9 L= 87 Time= 85.022 Sec.
I=10 L= 174 Time= 84.239 Sec.
I=11 L= 349 Time= 86.323 Sec.
I=12 L= 698 Time= 85.690 Sec.
I=13 L= 1396 Time= 84.695 Sec.
I=14 L= 2794 Time= 87.071 Sec.
I=15 L= 5588 Time= 87.726 Sec.
I=16 L= 11176 Time= 106.115 Sec.
I=17 L= 22353 Time= 108.253 Sec.
I=18 L= 44707 Time= 84.235 Sec.
I=19 L= 89415 Time= 83.708 Sec.
I=20 L= 178831 Time= 84.253 Sec.
I=21 L= 357662 Time= 83.539 Sec.
I=22 L= 715326 Time= 82.344 Sec.
I=23 L= 1430652 Time= 79.633 Sec.
I=24 L= 2861304 Time= 74.834 Sec.
End of main loop
End of calculation. Time= 2137.256 Sec.
End of data output. Time= 6.110 Sec.
Total calculation(I/O) time= 2143.366( 571.308) Sec.
------ Ended super_pi run : Fri Jan 8 19:15:15 CST 2010
real 36m23.268s
user 26m46.226s
sys 8m57.306s
So, 36.4 minutes to calculate, format and store 1+2^25 digits of Pi
(actually they throw in the initial 3. gratutiously...).
The host system was a Core 2 Duo running Red Hat Linux -
model name : Intel(R) Pentium(R) 4 CPU 3.00GHz
cpu MHz : 2992.654
cache size : 2048 KB
MemTotal : 1553460 kB
$ ja
version ''
Installer: j602a_linux32.sh
Engine: j602/2008-03-03/16:45
Library: 6.02.023java version "1.4.2" gij (GNU libgcj) version 4.1.2
20070626 (Red Hat 4.1.2-13)
$pifmt =. fread 'PI.DAT'
37312536
300 {. pifmt NB. Formatted output from Super Pi
PI=3.
1415926535 8979323846 2643383279 5028841971 6939937510 5820974944
5923078164 0628620899 8628034825 3421170679
8214808651 3282306647 0938446095 5058223172 5359408128 4811174502
8410270193 8521105559 6446229489 5493038196
4428810975 6659334461 2847564823 3786783165 2712019091 4564856692 3460
$pi =. pifmt -. 'PI= ',LF NB. Includes the initial 3 and the
decimal point.
33554434
2^25x
33554432
] pidigits =. 48 0 -"2 1~ (~. ,: #/.~) a.i.pi -. '.' NB. ASCII
codepoint for 0 is 48
3 1 4 5 9 2 6 8 7 0
3355076 3355566 3357258 3356382 3355866 3356627 3353819 3354116 3354632 3355091
hist =: ~. ,: #/.~ NB. histogram of numeric vector
shist =: ] {"1~ [: /: 0 { ] NB. sort on row 0 of matrix
rl =: [: #;.1~ 1 , 2 ~:/\ ] NB. run lengths
shist hist pirls =. rl pi-.'.' NB. run lengths of digits in pi
1 2 3 4 5 6 7 8 9
27181722 2718768 270560 27026 2684 286 34 1 1
shist (~. pirls),: (I. ~: pirls) { +/\pirls NB. First occurance
of run lengths
1 2 3 4 5 6 7 8 9
1 26 156 1593 17539 768 710107 22931753 24658610
(((I. ~: pirls) { +/\pirls) +/ i:10){pi-.'.' NB. show the first runs.
226097306314159265358
238462643383279502884
081284811174502841027
113499999983729780499
728909777727938000816
667680000010652624854
537333333386381390842
694444444436403113618
477777777724846769425
NB. First run above is a little confusing since 226097306
NB. is the last 9 of the 33554433 digits...
NB. Also a bit confusing is that Feynman's point occurs before
NB. runs of 4 and 5 digits.
~~~
Hours of fun playing with Pi.
You can find the SuperPi binaries for OS/X, Linux, and Windows with a
Google search.
If anyone wants the data I generated, I could make the 18 megabyte
zip file of the formatted version available to download, might be a
little quicker than generating it again, or maybe not....
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