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Code: Alles auswählen

p = sum(i for i in kassa if i > 0)
n = sum(kassa) - p

Code: Alles auswählen

import random
import sys
import time

if sys.version.startswith('3'):
    from functools import reduce
else:
    range = xrange

numbers = list(range(100000)) + list(range(-100000, 0))
random.shuffle(numbers)

def with_filter():
    t = time.time()
    sum(filter(lambda e: e > 0, numbers))
    sum(filter(lambda e: e < 0, numbers))
    return time.time() - t

def with_map():
    t = time.time()
    map(sum, zip(*((0, item) if item < 0 else (item, 0) for 
                   item in numbers)))
    return time.time() - t

def with_lc():
    t = time.time()
    sum(i for i in numbers if i<0)
    sum(i for i in numbers if i>0)
    return time.time() - t

def with_reduce():
    t = time.time()
    reduce(lambda pos_neg, next: (pos_neg[0] + next, pos_neg[1]) if
                  next >= 0 else (pos_neg[0], pos_neg[1] + next), 
                  numbers, (0, 0))
    return time.time() - t

def with_sub():
    t = time.time()
    p = sum(i for i in numbers if i > 0)
    sum(numbers) - p
    return time.time() - t

def with_for():
    t = time.time()
    result = [0, 0]
    for n in numbers:
        result[n<0] += n
    return time.time() - t

def start_test(count):
    t_filter, t_map, t_lc, t_reduce, t_sub, t_for = 0, 0, 0, 0, 0, 0
    for i in range(count):
        t_filter += with_filter()
        t_map += with_map()
        t_lc += with_lc()
        t_reduce += with_reduce()
        t_sub += with_sub()
        t_for += with_for()
    print ('filter: {0}\n'
           'map   : {1}\n'
           'lc    : {2}\n'
           'reduce: {3}\n'
           'sub   : {4}\n'
           'for   : {5}'.format(t_filter / count,
                                t_map / count,
                                t_lc / count, 
                                t_reduce / count, 
                                t_sub / count,
                                t_for / count))

if __name__ == '__main__':
    start_test(int(sys.argv[1]))

Code: Alles auswählen

$ python ./measure_sum.py 100
filter: 0.0847445440292
map   : 0.523688633442
lc    : 0.0519872546196
reduce: 0.0740648984909
sub   : 0.0361274647713
for   : 0.0377649760246

Code: Alles auswählen

python3 ./measure_sum.py 100
filter: 0.10626415252685546
map   : 0.3320684552192688
lc    : 0.06279780626296998
reduce: 0.08097020864486694
sub   : 0.04472310304641724
for   : 0.04908294916152954

Code: Alles auswählen

def start_test(count):
    functions = [func for name,func in globals().iteritems() if name.startswith('with_')]
    times = [0]*len(functions)
    for i in range(count):
        for idx, func in enumerate(functions):
            times[idx] += func()
    print '\n'.join('{0:6s}: {1}'.format(func.__name__.lstrip('with_'),t/count) for t,func in zip(times,functions))

Code: Alles auswählen

>>> def neg_pos(it):
...   n, p = 0, 0
...   for el in it:
...     if el<0:
...       n += el
...     else:
...       p += el
...   return n, p

Code: Alles auswählen

def start_test(count=5, repeat=3):
    functions = [func for name, func in globals().items() if 
                 name.startswith('with_')]
    result = {}
    timer = time.time
    for func in functions:
        import_ = 'from __main__ import {0}'.format(func.__name__)
        func_ = '{0}()'.format(func.__name__)
        results = timeit.repeat(stmt=func_, setup=import_, timer=timer, 
                                repeat=repeat, number=count)
        result[func.__name__] = min(results), max(results)
    result = sorted(result.items(), key=lambda e: e[0])
    print('{0} repetitions of {1} runs:'.format(repeat, count))
    print('\t\tmin\t\tmax')
    for func, times in result:
        print('{func}:\t{times[0]:f}\t{times[1]:f}'.format(times=times, 
                                                           func=func))

if __name__ == '__main__':
    args = map(int, sys.argv[1:3])
    start_test(*args)

Code: Alles auswählen

$ python ./measure_sum.py 10 5
5 repetitions of 10 runs:
             min         max
with_filter: 0.856682    0.864453
with_for:    0.387800    0.404242
with_ifelse: 0.282156    0.295538
with_lc:     0.529992    0.540703
with_map:    1.683503    1.728494
with_reduce: 0.761827    0.793188
with_sub:    0.369928    0.388947

Code: Alles auswählen

$ python3 ./measure_sum.py 10 5
5 repetitions of 10 runs:
             min         max
with_filter: 1.111608    1.166339
with_for:    0.493963    0.498310
with_ifelse: 0.407400    0.417205
with_lc:     0.630200    0.632272
with_map:    1.335373    1.345122
with_reduce: 0.807354    0.809970
with_sub:    0.453200    0.454332