primes from module primePy

This module contains several useful functions to work with prime numbers. For example, extracting all the prime factors (with multiplicity) of a positive integer reasonably fast. Following the list of all functions and their running time.

Getting started

Download the file primes.py and place it in the same directory where your python is installed. Or, simply run the command

>>>pip install primePy

to install the package. After either of the above two methods you can call it by

>>>from primePy import primes

and then execute the available methods.

Available methods

primes.check(n) returns True if n is a prime number.
primes.factor(n) returns the lowest prime factor of n.
primes.facors(n) returns all the prime factors of n with multiplicity.
primes.first(n) returns first n many primes.
primes.upto(n) returns all the primes less than or equal to n.
primes.between(m,n) returns all the primes between m and n.
primes.phi(n) returns the Euler's phi(n) i.e., the number of integers less than n which have no common factor with n.

Demonstration

This program is tested on my personal laptop with the following configurations.

Processor: Intel(R) Core(TM) i3-4030U CPU @ 1.90Ghz
Installed memory(RAM): 6.00GB
System type: 64 bit Operating System, x64-based processor
Operating system: Windows 10

Small numbers

All the following commands returnd results in less than 1 sec.

>>> primes.check(56156149)
False
>>> primes.check(79012338765433)
True

>>> primes.factor(7568945625)
3
>>> primes.factor(5141)
53

>>> primes.factors(252)
[2, 2, 3, 3, 7]
>>> primes.factors(44410608)
[2, 2, 2, 2, 3, 3, 11, 23, 23, 53]

>>> primes.first(7)
[2, 3, 5, 7, 11, 13, 17]
>>> primes.first(37)
[2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 37, 41, 43, 47, 53, 59, 61, 67, 71, 73, 79, 83,
89, 97, 101, 103, 107, 109, 113, 127, 131, 137, 139, 149, 151, 157]
>>> primes.first(5000)
[2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 37, 41, 43, 47, 53, 59, 61, 67, 71, 73, 79, 83,
89, 97, 101, 103, 107, 109, 113, 127, 131, 137, 139, 149, 151, 157, 163, 167, 173, 179,
. . . . 
. . . .
 48179, 48187, 48193, 48197, 48221, 48239, 48247, 48259, 48271, 48281, 48299, 48311, 48313, 48337, 48341, 48353, 48371, 48383, 48397, 48407, 48409, 48413, 48437, 48449, 48463, 48473, 48479, 48481, 48487, 48491, 48497, 48523, 48527, 48533, 48539, 48541, 48563, 48571, 48589, 48593, 48611]

Outcomes from the last command is truncated.

>>> primes.upto(16)
[2, 3, 5, 7, 11, 13]
>>> primes.upto(50000)
[2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 37, 41, 43, 47, 53, 59, 61, 67, 71, 73, 79, 83,
89, 97, 101, 103, 107, 109, 113, 127, 131, 137, 139, 149, 151, 157, 163, 167, 173, 179
. . .
. . .
49789, 49801, 49807, 49811, 49823, 49831, 49843, 49853, 49871, 49877, 49891, 49919,
49921, 49927, 49937, 49939, 49943, 49957, 49991, 49993, 49999]

>>> primes.between(100,200)
[101, 103, 107, 109, 113, 127, 131, 137, 139, 149, 151, 157, 163, 167, 173, 179, 181, 191, 193, 197, 199]
>>> primes.between(100000,500000)
[100003, 100019, 100043, 100049, 100057, 100069, 100103, 100109, 100129, 100151, 100153,
100169, 100183, 100189, 100193, 100207, 100213, 100237, 100267, 100271, 100279, 100291

499661, 499663, 499669, 499673, 499679, 499687, 499691, 499693, 499711, 499717, 499729, 499739, 499747, 499781, 499787, 499801, 499819, 499853, 499879, 499883, 499897, 499903, 499927, 499943, 499957, 499969, 499973, 499979]

>>> primes.phi(128)
64
>>> primes.phi(561534567567457)
483618287856960

A little bigger numbers

All the following commands returned results in less than 5 secs.

>>> primes.factors(2910046587320501324077792713140104371205630933992706145011)
[239, 701, 709, 1997, 1997, 3889, 5171, 5171, 6983, 10009, 4940867, 45845791, 3731292319]

>>> primes.first(10000)[9999]
104729

The last command returns the 10000th prime.

Suggestions

Feel free to drop your suggestion at the following email address

Author: Indrajit Jana
Email: ijana at temple dot edu