Re: [Haskell-beginners] Performance of Prime Generator

Well, thanks, so far I have tried wheel only and Sieve of Eratosthenes only approaches. They both failed. When the numbers is between 999900000 and 1000000000, they can take more than a hour on my laptop. On Jan 21, 2012, at 10:38 PM, Ertugrul Söylemez wrote:

Zhi-Qiang Lei wrote:

...

Hi, what do you mean "more naive wheel trial division"?

Just use a wheel like 2*3*5 and don't bother only dividing by primes. Trying to divide only by primes takes more time than just living with the few percent nonprimes that slip through the wheel.

Or better yet, use a sieve like the Sieve of Eratosthenes or the Sieve of Atkin. Those are fairly easy to implement in Haskell.

Greets, Ertugrul

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Best regards, Zhi-Qiang Lei zhiqiang.lei@gmail.com