I'm not sure why people keep propogating the one where you have to multiply by 4. It's much simpler to say: 
my $pi = atan2(0,-1);

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In other words, don't create a vector that points at 45 degrees and multiply by 4... create a vector that points at 180 degrees!

-- Randal L. Schwartz, Perl hacker
Be sure to read my standard disclaimer if this is a reply.

In reply to •Re: Re: Deriving pi and e by merlyn
in thread Deriving pi and e by fredopalus

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