Question

该程序将分析不同情况下的不同排序算法。我想存储算法名称，我需要为案例（a）存储10个运行时间值，然后分别存储10个运行值，用于案例（b）下面是测试不同排序算法运行时的代码。我的代码在每个算法启动后都会丢失结果，因为我不知道如何正确存储它们

def call(m):
    for i in range(m):
        makelist()

def makelist():
    lst=[10]
    for l in lst:
        testall(l)

def testall(n):
    flist = [insertionsort,selectionsort]
    if n < 1:
        n = 1
    testlist = [i for i in range(n)]
    lsr=[testlist.sort(),   testlist.sort(reverse=True),random.shuffle(testlist)]
    for f in flist:
        result=[]
        for g in lsr:
            copylist = copy.deepcopy(testlist)
            testfunction(copylist,f, result)

def testfunction(testlist, function,r):
    start_time = time.perf_counter()
    function(testlist)
    end_time = time.perf_counter()
    print('time =', (end_time - start_time), '; alg =', function.__name__, '(', len(testlist), ')')
    r.append(end_time - start_time)

Answer 1

根据您的大纲，我建议使用列表的默认值，其中函数名称是键，并且各种计时附加到值：

from collections import defaultdict

def testfunction(testlist, function, results):
    start_time = time.perf_counter()
    function(testlist)
    end_time = time.perf_counter()
    print('time =', (end_time - start_time), '; alg =', function.__name__, '(', len(testlist), ')')
    results[function.__name__].append(end_time - start_time)


results = defaultdict(list)

for f in flist:
    for g in lsr:
        copylist = copy.deepcopy(testlist)
        testfunction(copylist, f, results)

当您完成后，结果将包含以下内容：

>>> results
defaultdict(<class 'list'>, {'haresort': [6.194799953483277, 1.947999534832776, 9.47999534832776, 4.799953483277619, 7.999534832776194, 6.194799953483277, 1.947999534832776, 9.47999534832776, 4.799953483277619, 7.999534832776194], 'snailsort': [8.327761947999534, 3.277619479995348, 2.776194799953483, 7.761947999534832, 7.619479995348327, 8.327761947999534, 3.277619479995348, 2.776194799953483, 7.761947999534832, 7.619479995348327]})

在大多数情况下，只需将defaultdict视为普通字典即可。例如，作为testall（）中的最后一件事，您可以打印出结果的内容：

for function, timings in results.items():
    print(function, ":\n")
    print(*timings, sep="\n")
    print()

什么是存储算法时间的最佳方法

1 个答案: