"Damien R. Sullivan" wrote: <snip>

Then I moved to Haskell, largely rewriting the ML code. The result is much nicer looking, being able to say 'sum + powx' instead of 'Num.add_num sum powx', or having to define 'num_2' for a bignum version of 2. It took longer to actually run properly -- I got bit by laziness, but John Meacham tipped me off. And now I have '34283788463231218 % 20536892788086675' being printed out, although I seem to have a bug since if that's a numerator and denominator the result is not the natural logarithm of 2. But my real question is can I get Haskell to actually do that division itself? I get complaints about 'Fractional Integer'; I had to use bc to do the division.

Sure:

rationalToDouble :: Rational -> Double rationalToDouble rat = fromInteger (numerator rat) / fromInteger (denominator rat)

HTH

-xx- Damien X-)

Jon Cast