4 Feb
2009
4 Feb
'09
5:08 p.m.
On Wed, Feb 4, 2009 at 2:03 PM, Manlio Perillo
Max Rabkin ha scritto:
[...]
Then we can define (/.) :: (Real a1, Real a2, Fractional a) => a1 -> a2 -> a x /. y = fromRational $ toRational x / toRational y
[...]
(//) :: (Integral b, Real a, Real a1) => a -> a1 -> b x // y = floor $ toRational x / toRational y
Hope that helps, Max
Yes, thanks.
However there is still a *big* problem: it is inefficient.
It sure is. To get the type you asked for, one *has* to go via rationals. But...
Here is an Haskell version: http://paste.pocoo.org/show/102801/
On my system it takes 30 seconds.
You're only dividing integers by integers to get Doubles. x /. y = fromIntegral x / fromIntegral y works just fine in this case. --Max