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[Python-Dev] PEP239 (Rational Numbers) Reference Implementation and new issues
Peter Norvigpeter@norvig.com
Thu, 03 Oct 2002 13:15:01 -0700
I agree with pinard, although I think it is a manageable problem. I went through this transition once, from Symbolics Lisp, in which integer division truncates, to Common Lisp, in which it produces a rational. After only an hour or two of fiddling with my various programs, everything seemed to work; I was very happy. But after a few days, the machine started to slow down mysteriously, especially on wake-up. It took a while to discover the culprit was my screensaver program (which I hadn't checked) -- it was displaying fish on the screen, and the coordinates of the fish had become rationals quotients of thousand-digit numbers.-Peterpinard@iro.umontreal.ca writes: > While I agree with the theoretical arguments, I have the practical fear that > rationals could grow very big, rather quickly, in the course of a long > computation involving them in various ways. By big, I mean the numerator > and denominator of the fraction taken in isolation, not the number itself.
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