Moduleprimes-0.2.1.0Haskell98

Data.Numbers.Primes

This Haskell library provides an efficient lazy wheel sieve for prime generation inspired by Lazy wheel sieves and spirals of primes by Colin Runciman (http://www.cs.york.ac.uk/ftpdir/pub/colin/jfp97lw.ps.gz) and The Genuine Sieve of Eratosthenes by Melissa O'Neil (http://www.cs.hmc.edu/~oneill/papers/Sieve-JFP.pdf).

4 values

Packageprimes-0.2.1.0
Exports4
LanguageHaskell98
LicenceBSD-3-Clause
SourcePrimes.hs

valueprimes :: Integral int => [int]

This global constant is an infinite list of prime numbers. It is generated by a lazy wheel sieve and shared across the whole program run. If you are concerned about the memory requirements of sharing many primes you can call the function wheelSieve directly.

valuewheelSieve

:: Integral int
=> Int
number of primes canceled by the wheel
-> [int]
infinite list of primes

This function returns an infinite list of prime numbers by sieving with a wheel that cancels the multiples of the first n primes where n is the argument given to wheelSieve. Don't use too large wheels. The number 6 is a good value to pass to this function. Larger wheels improve the run time at the cost of higher memory requirements.

valueisPrime :: Integral int => int -> Bool

Checks whether a given number is prime.

This function uses trial division to check for divisibility with all primes below the square root of the given number. It is impractical for numbers with a very large smallest prime factor.

valueprimeFactors :: Integral int => int -> [int]

Yields the sorted list of prime factors of the given positive number.

This function uses trial division and is impractical for numbers with very large prime factors.