On 2004-10-27 at 19:37+0900 Stijn De Saeger wrote: > hello > > Thanks for the explanation, at first it seemed like enumFromThenTo > would indeed give me the functionality I am looking for. But then all > of GHCi started acting weird while playing around... this is a > copy-paste transcript from the terminal. > > *S3> 0.5 `elem` [0.0,0.1..1.0] > True > *S3> 0.8 `elem` [0.6,0.7..1.0] > False > *S3> 0.8 `elem` [0.6,0.7..1.0] > False > *S3> [0.6,0.7..0.9] > [0.6,0.7,0.7999999999999999,0.8999999999999999] > *S3> > > ????????
> why would the floating point step size work the first time but not the > second? confusing... Doubles aren't real numbers, they're binary floating point. 1/5 doesn't have a finite binary representation. Also what gets printed out has been converted back to decimal and rounded a bit. So don't expect too much from them! You probably want to use Double -> Bool, and possibly look at infinite precision real arithmetic too. J�n -- J�n Fairbairn [EMAIL PROTECTED] _______________________________________________ Haskell-Cafe mailing list [EMAIL PROTECTED] http://www.haskell.org/mailman/listinfo/haskell-cafe
