2

我正在尝试计算气泡和插入排序的时间。排序对它们都很好，但它输出需要 15 秒，这显然是不正确的。任何建议如何解决这个问题？

# insertion sort
x = [7, 2, 3, 5, 9, 1]

def insertion(list):
    for index in range(1,len(list)):
        value = list[index]
        i = index - 1
        while i>=0 and (value < list[i]):
            list[i+1] = list[i] # shift number in slot i right to slot i+1
            list[i] = value # shift value left into slot i
            i = i - 1

# bubble sort
y = [7, 2, 3, 5, 9, 1]

def bubble(unsorted_list):
    length = len(unsorted_list) - 1
    sorted = False

    while not sorted:
        sorted = True
        for i in range(length):
            if unsorted_list[i] > unsorted_list[i+1]:
                sorted = False
                unsorted_list[i], unsorted_list[i+1] = unsorted_list[i+1], unsorted_list[i]

def test():
    bubble(y)
    insertion(x)

if __name__ == '__main__':
    import timeit
    print(timeit.timeit("test()", setup="from __main__ import test"))
4

3 回答 3

5

从timeit文档中：

timeit.timeit (stmt='pass', setup='pass', timer=, number=1000000)

使用给定的语句、设置代码和计时器函数创建一个 Timer 实例，并运行其 timeit() 方法并执行次数。

所以你的代码运行了 1,000,000 次。将返回值除以10**6，您就可以上路了。

于 2013-04-11T19:47:08.403 回答
0

profile也是您可以考虑的一个选项。

于 2013-04-11T19:59:41.890 回答
-1

试试这个，你捕获当前时间，执行函数，然后从当前时间中减去之前捕获的时间。

# insertion sort
x = [7, 2, 3, 5, 9, 1]

def insertion(list):
    for index in range(1,len(list)):
        value = list[index]
        i = index - 1
        while i>=0 and (value < list[i]):
            list[i+1] = list[i] # shift number in slot i right to slot i+1
            list[i] = value # shift value left into slot i
            i = i - 1

# bubble sort
y = [7, 2, 3, 5, 9, 1]

def bubble(unsorted_list):
    length = len(unsorted_list) - 1
    sorted = False

    while not sorted:
        sorted = True
        for i in range(length):
            if unsorted_list[i] > unsorted_list[i+1]:
                sorted = False
                unsorted_list[i], unsorted_list[i+1] = unsorted_list[i+1], unsorted_list[i]

def test():
    start = time.clock()
    bubble(y)
    elapsed = (time.clock() - start)
    print "Time taken for bubble = ", elapsed
    start = time.clock()
    insertion(x)
    elapsed = (time.clock() - start)
    print "Time taken for Insertion = ", elapsed

if __name__ == '__main__':
    import time
    test()
于 2013-04-11T19:48:58.910 回答