Wise monks,

I'm running the same calculation with and without the bignum pragma. With the bignum pragma, I get an incorrect result. Could you explain me why? 

$ perl -we 'print atan2(1, 0), $/, atan2(0, 1), $/;'
1.5707963267949
0
$ perl -we 'use bignum; print atan2(1, 0), $/, atan2(0, 1), $/;'
0
1.5707963267949

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My perl is v5.8.5 built for i686-linux.

Update: I was fiddling with this snippet: Approximation with chain fractions when I found this.

Update: Tels has fixed this bug in Math::BigInt v1.75 (2005-03-20). Upgrade your Math::BigInt package if you are affected by this bug. Thanks.

In reply to wrong results of atan2 with bignum by ambrus

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