Re: [Haskell-cafe] Looking for the fastest Haskell primes algorithm

2009-04-19 Thread ajb
G'day all. Quoting Dan Weston : Unless primesUpTo n goes from highest to lowest prime (ending in 2), I don't see how sharing is possible (in either space or time) between primesUpTo for different n. Given that it's a mistake for a library to leak memory, there are essentially three possibilit

Re: [Haskell-cafe] Looking for the fastest Haskell primes algorithm

2009-04-16 Thread Dan Weston
Unless primesUpTo n goes from highest to lowest prime (ending in 2), I don't see how sharing is possible (in either space or time) between primesUpTo for different n. Is it intended that the primes should therefore be listed in descending order? a...@spamcop.net wrote: primes :: [Integer]

Re: [Haskell-cafe] Looking for the fastest Haskell primes algorithm

2009-04-16 Thread ajb
G'day all. Quoting Eugene Kirpichov : I'd suggest also primesFrom :: Integer -> [Integer] This: primes :: [Integer] isn't as useful as you might think for a library, because it must, by definition, leak an uncontrolled amount of memory. This: primesUpTo :: Integer -> [Integer] is a bett

Re: [Haskell-cafe] Looking for the fastest Haskell primes algorithm

2009-04-16 Thread Sebastian Fischer
On Apr 15, 2009, at 5:27 PM, Adrian Neumann wrote: I've just uploaded a package with some functions I had lying around. > http://hackage.haskell.org/cgi-bin/hackage-scripts/package/Numbers This package seems to be missing the source file Data/Numbers/ Primes.hs so I couldn't compare it to m

Re: [Haskell-cafe] Looking for the fastest Haskell primes algorithm

2009-04-15 Thread Adrian Neumann
I've just uploaded a package with some functions I had lying around. > http://hackage.haskell.org/cgi-bin/hackage-scripts/package/Numbers Am 14.04.2009 um 14:40 schrieb Niemeijer, R.A.: Today I happened to need a large list of prime numbers. Obviously this is a well-known problem, so I figur

Re: [Haskell-cafe] Looking for the fastest Haskell primes algorithm

2009-04-15 Thread Lennart Augustsson
For isPrime you might want to implement the AKS test, http://en.wikipedia.org/wiki/AKS_primality_test On Tue, Apr 14, 2009 at 3:05 PM, Edward Kmett wrote: > You might want to start with the Sieve of Atkin: > > http://en.wikipedia.org/wiki/Sieve_of_Atkin > > -Edward > > On Tue, Apr 14, 2009 at 8:4

Re: [Haskell-cafe] Looking for the fastest Haskell primes algorithm

2009-04-15 Thread wren ng thornton
Edward Kmett wrote: You might want to start with the Sieve of Atkin: http://en.wikipedia.org/wiki/Sieve_of_Atkin Also worth reading _Lazy wheel sieves and spirals of primes_: http://www.cs.york.ac.uk/ftpdir/pub/colin/jfp97lw.ps.gz -- Live well, ~wren _

Re: [Haskell-cafe] Looking for the fastest Haskell primes algorithm

2009-04-14 Thread Michael Matsko
ot; , haskell-cafe@haskell.org Sent: Tuesday, April 14, 2009 12:35:19 PM GMT -05:00 US/Canada Eastern Subject: Re: [Haskell-cafe] Looking for the fastest Haskell primes algorithm On Tue, Apr 14, 2009 at 2:47 PM, Andrew Wagner wrote: > Some other ideas for things to put in this package pos

Re: [Haskell-cafe] Looking for the fastest Haskell primes algorithm

2009-04-14 Thread Max Rabkin
On Tue, Apr 14, 2009 at 2:47 PM, Andrew Wagner wrote: > Some other ideas for things to put in this package possibly: > is_prime :: Int -> Bool I'd also add isProbablePrime using a Miller-Rabin test or somesuch, for use with large numbers. It'd have to be in a monad which supplies randomness, of c

Re: [Haskell-cafe] Looking for the fastest Haskell primes algorithm

2009-04-14 Thread Edward Kmett
You might want to start with the Sieve of Atkin: http://en.wikipedia.org/wiki/Sieve_of_Atkin -Edward On Tue, Apr 14, 2009 at 8:40 AM, Niemeijer, R.A. 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

Re: [Haskell-cafe] Looking for the fastest Haskell primes algorithm

2009-04-14 Thread Martijn van Steenbergen
Niemeijer, R.A. wrote: 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. Excellen

Re: [Haskell-cafe] Looking for the fastest Haskell primes algorithm

2009-04-14 Thread Eugene Kirpichov
I'd suggest also primesFrom :: Integer -> [Integer] and probably a separate function nextPrime :: Integer -> Integer 2009/4/14 Andrew Wagner : > Some other ideas for things to put in this package possibly: > is_prime :: Int -> Bool > nth_prime :: Int -> Int -- or Int -> Integer > prime_factors

Re: [Haskell-cafe] Looking for the fastest Haskell primes algorithm

2009-04-14 Thread Andrew Wagner
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 throug

[Haskell-cafe] Looking for the fastest Haskell primes algorithm

2009-04-14 Thread Niemeijer, R.A.
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