Re: [Haskell-cafe] Re: Is logBase right?

Prelude> toRational 697.04157958259998 3065621287177675 % 4398046511104 Prelude> toRational 697.0415795826 3065621287177675 % 4398046511104 As you can see, both numbers are represented by the same Double. Haskell prints a Double with the simplest number that converts back to the same bit pattern. So there's no "keep more decimals", just a matter of string conversion. -- Lennart On Tue, Aug 25, 2009 at 7:11 PM, Ketil Malde wrote:

Steve writes:

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Also, I had a problem using floating point in Python where

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round(697.04157958254996, 10) gave 697.04157958259998

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Its been fixed in the latest versions of Python:

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round(697.04157958254996, 10) 697.0415795825

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ghci> roundN 697.04157958254996 10 697.0415795826

Is there something special with this number?

 Python 2.6.2 (release26-maint, Apr 19 2009, 01:56:41)  [GCC 4.3.3] on linux2  Type "help", "copyright", "credits" or "license" for more information.  >>> 697.04157958259998  697.04157958259998  >>> 12345.678901234567890  12345.678901234567

 GHCi, version 6.8.2: http://www.haskell.org/ghc/  :? for help  Loading package base ... linking ... done.  Prelude> 697.04157958259998  697.0415795826  Prelude> 12345.678901234567890  12345.678901234567

So, Python manages to keep more decimals than GHC for your number, but for other numbers, the precision appears to be the same.

-k -- If I haven't seen further, it is by standing in the footprints of giants _______________________________________________ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe