麻烦老师和同学解释一下date=[1]*{},谢谢你们了

whwJava12306

源代码如下：


        import timeit

common_for = """
for d in data:
    s += d
"""

common_sum = """
sum(data)
"""

common_numpy_sum = """
numpy.sum(data)
"""

def timeit_list(n, loops):
    list_setup = """
import numpy
data = [1] * {}
s = 0
""".format(n)
    print 'list:'
    print timeit.timeit(common_for, list_setup, number = loops)
    print timeit.timeit(common_sum, list_setup, number = loops)
    print timeit.timeit(common_numpy_sum, list_setup, number = loops)

def timeit_array(n, loops):
    array_setup = """
import numpy
import array
data = array.array('L', [1] * {})
s = 0
""".format(n)
    print 'array:'
    print timeit.timeit(common_for, array_setup, number = loops)
    print timeit.timeit(common_sum, array_setup, number = loops)
    print timeit.timeit(common_numpy_sum, array_setup, number = loops)

def timeit_numpy(n, loops):
    numpy_setup = """
import numpy
data = numpy.array([1] * {})
s = 0
""".format(n)
    print 'numpy:'
    print timeit.timeit(common_for, numpy_setup, number = loops)
    print timeit.timeit(common_sum, numpy_setup, number = loops)
    print timeit.timeit(common_numpy_sum, numpy_setup, number = loops)

if __name__ == '__main__':
    timeit_list(50000, 500)
    timeit_array(50000, 500)
    timeit_numpy(50000, 500)


运行结果如下：
        C:\Python27\python.exe C:/baokao/moran.py
list:
2.37343969091
0.529917385451
2.79953571604
array:
4.50627483278
3.4106598665
11.5509814123
numpy:
10.0953783914
8.69785286165
0.0284571073942

ooxx7788

跟着下面的.format(n)看啊，这个{}就是n

ButcherRabbit

ooxx7788 发表于 2017-6-27 18:23
跟着下面的.format(n)看啊，这个{}就是n

支持大佬！！！！

whwJava12306

ooxx7788 发表于 2017-6-27 18:23
跟着下面的.format(n)看啊，这个{}就是n

谢谢您啊！