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iterating over strings seems to be really slow?

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*I'm confused why the former function runs significantly faster when
wc1() builds the hash on a single pass and doesn't waste memory of
returning an array of strings? *

*I would think wc2() to be slower what's going on here? *


#!/usr/bin/env python

s = "The black cat jump over the bigger black cat"


def wc1():

    word=""

    m={}

    for c in s:

        if c != " ":
            word += c
        else:
            if m.has_key(word):
                m[word] += 1
            else:
                m[word] = 1
            word=""


    return(m)



def wc2():

    m={}

    for c in s.split():
        if m.has_key(c):
            m[c] += 1
        else:
            m[c] = 1
    return(m)

if __name__ == '__main__':
    import timeit
    print(timeit.timeit("wc1()", setup="from __main__ import wc1"))
    print(timeit.timeit("wc2()", setup="from __main__ import wc2"))

⮀python wordcount.py
7.39647197723
3.15220093727

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iterating over strings seems to be really slow? Rodrick Brown <rodrick.brown@gmail.com> - 2014-08-27 16:53 -0400

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