I'd suggest also primesFrom :: Integer -> [Integer]
and probably a separate function nextPrime :: Integer -> Integer 2009/4/14 Andrew Wagner <[email protected]>: > Some other ideas for things to put in this package possibly: > is_prime :: Int -> Bool > nth_prime :: Int -> Int -- or Int -> Integer > prime_factors :: Int -> [Int] > > I'm assuming there are faster ways of doing the first 2 than by just simply > looking through all of primes. Someone should also look through Euler - I'm > sure that will generate other ideas of things that could be useful in > playing with primes. > On Tue, Apr 14, 2009 at 8:40 AM, Niemeijer, R.A. <[email protected]> > wrote: >> >> Today I happened to need a large list of prime numbers. Obviously this is >> a well-known problem, so I figured there would be something on Hackage that >> I could use. Surprisingly, there isn’t, or if there is it’s not easy to >> find. Searching for prime or primes on Hackage reveals nothing. Searching >> for primes on Hayoo gives Codec.Encryption.RSA.NumberTheory, but that uses >> the inefficient one-liner implementation. The HaskellWiki article on primes >> (http://www.haskell.org/haskellwiki/Prime_numbers) has a number of >> implementations, but the faster they get, the longer and uglier they become. >> >> >> >> Since it’s such a common problem I’d say it would be a good idea to add a >> package to Hackage that exports >> >> primes :: [Integer] >> >> and hides the ugly implementation details. Data.Numbers.Primes seems a >> logical choice for the namespace, but I’m open to suggestions. >> >> >> >> The trick then is to find the most efficient implementation of primes. The >> Haskell wiki article mentions ONeillPrimes.hs as one of the fastest ones, >> but maybe there’s a faster version. So my question is: does anybody know >> what the fastest Haskell algorithm for generating primes is? >> >> _______________________________________________ >> Haskell-Cafe mailing list >> [email protected] >> http://www.haskell.org/mailman/listinfo/haskell-cafe >> > > > _______________________________________________ > Haskell-Cafe mailing list > [email protected] > http://www.haskell.org/mailman/listinfo/haskell-cafe > > -- Eugene Kirpichov Web IR developer, market.yandex.ru _______________________________________________ Haskell-Cafe mailing list [email protected] http://www.haskell.org/mailman/listinfo/haskell-cafe
