At long last, I am pleased to announce the latest version of PyPrimes, a pure Python package for working with prime numbers.
PyPrimes is compatible with Python 2 and 3, and includes multiple algorithms for the generating and testing of prime numbers, including the Sieve of Eratosthenes, Croft Spiral, Miller-Rabin and Fermat probabilistic tests. https://pypi.python.org/pypi/pyprimes/ Examples ======== Generate prime numbers on demand: py> it = pyprimes.primes() py> next(it) 2 py> next(it) 3 Test whether numbers are prime: py> pyprimes.is_prime(23) True Generate primes between an upper and lower limit: py> import pyprimes py> list(pyprimes.primes(11000000, 11000500)) [11000027, 11000053, 11000057, 11000081, 11000083, 11000089, 11000111, 11000113, 11000149, 11000159, 11000179, 11000189, 11000273, 11000281, 11000287, 11000291, 11000293, 11000299, 11000347, 11000351, 11000369, 11000383, 11000387, 11000393, 11000399, 11000401, 11000419, 11000441, 11000461, 11000467] Find the previous and next primes from a given value: py> pyprimes.prev_prime(10**9) 999999937 py> pyprimes.next_prime(999999937) 1000000007 Find the prime factorisation of small numbers: py> import pyprimes.factors py> pyprimes.factors.factorise(999999997) [71, 2251, 6257] Pyprimes also includes examples of naive and poor-quality, but popular, algorithms which should be avoided: py> from pyprimes.awful import turner py> it = turner() py> [next(it) for i in range(20)] [2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 37, 41, 43, 47, 53, 59, 61, 67, 71] Study the source code of the "awful" module to see what not to do! Performance =========== As PyPrimes is written entirely in Python, it is not suitable for demanding high-performance applications, but performance can be quite reasonable for less-demanding applications. On a laptop with a AMD Turion (tm) II P520 Dual-Core Processor, it takes 0.005 second to generate the first prime larger than 2**63, and about 10 seconds to generate the first one million primes. Testing whether 2**63+7 is prime takes under 0.1 millisecond. Installing PyPrimes =================== You can download PyPrimes from here: https://pypi.python.org/pypi/pyprimes/ For Windows users, run the installer. For Linux, Mac and Unix users, unpack the source tar ball and follow the instructions. You can also install using pip: pip install pyprimes==0.2.1a (Note: pip may have problems downloading the right version if you don't specify a version number.) Or you can access the latest development version: hg clone https://code.google.com/p/pyprimes/ -- Steve -- https://mail.python.org/mailman/listinfo/python-list
