royqh1979/pymapreduce

A Multi-processing based single-host MapReduce Framework

This is a simple mapreduce framework.

Sample program

from mapreduce import *
from math import ceil, sqrt


def mapper_2(item):
    return (item + 5) * 23 - 1


def reducer_2(accumulated, item):
    return accumulated + item


def is_prime(n):
    for i in range(2, ceil(sqrt(n))):
        if n % i == 0:
            return False
    return True


if __name__ == "__main__":
    N = 150000
    print('* map & reduce ')
    mr = MapReducer().prefilter(is_prime).mapper(mapper_2).reducer(reducer_2, 0)
    result = mr(range(N))
    print('  MR Result  :', result)
    n = sum([(n + 5) * 23 - 1 for n in range(N) if is_prime(n)])
    print('  Validation:', n)