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Changing a global variable with multiprocessing in python

So what I'm trying to do ultimately is read the line, do some calculations with the information in that line, and then add the result to some global object, but I can never get it to work. For example, the test is always 0 in the code below. I know this is wrong, and I tried to do it differently, but it still does not work.

import multiprocessing as mp

File = 'HGDP_FinalReport_Forward.txt'
#short_file = open(File)
test = 0

def pro(temp_line):
    global test
    temp_line = temp_line.strip().split()
    test = test + 1
    return len(temp_line)

if __name__ == "__main__":
    with open("HGDP_FinalReport_Forward.txt") as lines:
        pool = mp.Pool(processes = 10)
        t = pool.map(pro,lines.readlines())
+5
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2 answers

, , . , . - test , . . - (untested):

def pro(temp_line):
    test = 0
    temp_line = temp_line.strip().split()
    test = test + 1
    return test, len(temp_line)

if __name__ == "__main__":
    with open("somefile.txt") as lines:
        pool = mp.Pool(processes = 10)
        tests_and_t = pool.map(pro,lines.readlines())
        tests, t = zip(*test_and_t)
        test = sum(tests)
+15

.

, :

import multiprocessing
import time
import os
import sys
import random
def worker(a):
    oldValue = get()
    set(random.randint(0, 100))
    sys.stderr.write(' '.join([str(os.getpid()), str(a), 'old:', str(oldValue), 'new:', str(get()), '\n']))

def get():
    global globalVariable
    return globalVariable

globalVariable = -1
def set(v):
    global globalVariable
    globalVariable = v

print get()
set(-2)
print get()

processPool = multiprocessing.Pool(5)
results = processPool.map(worker, range(15))

:

27094 0 old: -2 new: 2 
27094 1 old: 2 new: 95 
27094 2 old: 95 new: 20 
27094 3 old: 20 new: 54 
27098 4 old: -2 new: 80 
27098 6 old: 80 new: 62 
27095 5 old: -2 new: 100 
27094 7 old: 54 new: 23 
27098 8 old: 62 new: 67 
27098 10 old: 67 new: 22 
27098 11 old: 22 new: 85 
27095 9 old: 100 new: 32 
27094 12 old: 23 new: 65 
27098 13 old: 85 new: 60 
27095 14 old: 32 new: 71
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