CODEWITHSUNDEEP
pythonmultiprocessing
Caio Navarro
Caio Navarro

Reputation: 58

Python multiprocessing library thinks multilettered args are multiple args

Ive been trying to program this piece of code that analsizes stocks and whenenver i try to pass a stock symbol such as "GOOG" trought multiproccess it takes each letter of "GOOG" as a different argument.

import multiprocessing as mp

def main():
    for value in stocks:
        
        p = mp.Process(target=nnfuncs.compare, args=value["symbol"])
        
        p.start()
        nnstruct.processes.append(p) 
        
    for process in nnstruct.processes:
        process.join()

if __name__ == '__main__':
    main()

The "stocks" var contains "AWP" "ACP" "JEQ" "ASGI" "AOD".

If i were to run that it would tell me that "TypeError: compare() takes 1 positional argument but 4 were give" even though those are all one arguments, it multiproccesing takes it as each letter of the symbol is one different argument.

Upvotes: 0

Views: 36

Answers (1)

M.O.
M.O.

Reputation: 2911

The args parameter in multiprocessing.Process are interpreted as a tuple (see the documentation), so your text arguments are being interpreted as tuple("AWP") == ("A", "W", "P"). You probably want to pass your argument as args=(value["symbol"],).

Upvotes: 2

Related Questions