one-liner pi

I always love implementing this (++ if you can tell where the algorithm comes from!)

for($|++,$_++,$a++;;$,+=$a/$_,$_++,$a*=-1,$_++){printf"%.16f\n",$,*4}
[download]

This version will run (incessantly) as a one-liner as well. -zeno

Update: As MrNobo1024 has answered correctly, this algorithm was discovered by Gregory and Leibniz.

Comment on one-liner pi Download Code

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Re: one-liner pi by japhy (Canon) on Feb 15, 2001 at 00:43 UTC
It's the method for calculating arc-tan of 1. `japhy` -- Perl and Regex Hacker	[reply]
Re: Re: one-liner pi by zeno (Friar) on Feb 15, 2001 at 14:37 UTC
Hi japhy, Correct! I'm still looking for a little something more, though (I did ++ you). This algorithm historically is attributed to someone. Do you know who that someone is? (Hint: He's dead) -zeno	[reply]
Re: Re: Re: one-liner pi by MrNobo1024 (Hermit) on Feb 15, 2001 at 20:57 UTC
Gregory and Leibniz both discovered that formula.	[reply]
Re: (MrNobo1024) one-liner pi by zeno (Friar) on Feb 16, 2001 at 00:31 UTC
Re: one-liner pi by life_monger (Hermit) on Feb 17, 2001 at 00:29 UTC
TIMTOWTDI... I think I preserved the "spirit" of the algorithm :-) `#!/usr/bin/perl -w use strict; {(redo)while(printf"%.16f\n",$,+=((-1/++$_/(($a\|\|=1)=($_-$_++)-1)))* +4)}` [download]	[reply] [d/l]
Re: one-liner pi by MrNobo1024 (Hermit) on Feb 15, 2001 at 03:24 UTC
You should do a $\|++ before the program starts, or it won't display anything until you exit :(	[reply]
Re: Re: one-liner pi by zeno (Friar) on Feb 15, 2001 at 14:34 UTC
Hi MrNobo1024, It didn't happen that way for me... I thought that print did line buffering if it was printing to the terminal, and block buffering when printing to a filehandle. However... it nicely obfuscates the code a little more if I do put it in! So I did. Thanks for the tip! ;) -zeno	[reply]