On Thu, Jan 31, 2013 at 08:32:53AM -0500, Noah Lavine wrote:
     What you have here is a precision problem.
     
     scheme@(guile-user)> (= 3.14159265358979 (atan 0 -1))
     $8 = #f
     scheme@(guile-user)> (= $7 (atan 0 -1))
     $9 = #t
     
     It might be possible to have Guile print more digits and make this problem
     go away.
     
     Noah Lavine

pi is an irrational number.  You would need an infinite number of digits wouldn't you?

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