Skip to content

sylhare/nprime

Folders and files

NameName
Last commit message
Last commit date

Latest commit

 

History

67 Commits
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

Repository files navigation

nprime

PyPI version Build Status codecov Codacy Badge

Installation

To install the package use pip:

pip install nprime

Introduction

Some algorithm on prime numbers.

Algorithm developed :

  • Native one (prime through divisions)
  • Eratosthenes sieve based
  • Fermat's test (based on Fermat's theorem)
  • Prime generating functions
  • Miller Rabin predictive algorithm

Specifications

  • Language: Python 3.5.2
  • Package:
    • Basic python packages were preferred
    • Matplotlib v2.0 - graph and math

Continuous integration

Travis will be used to run the tests automatically.

Code Quality

Ensured with PEP-8 (for the language format) and Pylint (for the code quality). PyLint is now only run by an other review tool integrated to this repo (codacity, erbert, ...)

Math

Here are a bit of information to help understand some of the algorithms

Congruence

"" means congruent, a ≡ b (mod m) implies that m / (a-b), ∃ k ∈ Z that verifies a = kn + b

which implies:

a ≡ 0 (mod n) <-> a = kn <-> "a" is divisible by "n" 

Fermart's Theorem

if n is prime then ∀ a ∈[1, ..., n-1]

a^(n-1) ≡ 1 (mod n) ⇔ a^(n-1) = kn + 1

Miller rabin

Take a random a ∈ {1,...,n−1} and n > 2,
Find d and s such as with n - 1 = 2^s * d (with d odd)
if (a^d)^2^r ≡ 1 mod n for all r in 0 to s-1
Then n is prime.

The test output is false of 1/4 of the "a values" possible in n, so the test is repeated t times.

Strong Pseudoprime

A strong pseudoprime to a base a is an odd composite number n with n-1 = d·2^s (for d odd) for which either a^d = 1(mod n) or a^(d·2^r) = -1(mod n) for some r = 0, 1, ..., s-1