Question

我有以下格式的字典：

folders = {'Master folder': ['Training'], 'Child folder': ['Training videos', 'Training documents', 'Training workouts', 'Training practicals']}

我希望计算以下期望值，

count_of_masterfolder = 1
count_of_childfolder = 4

到目前为止，我做到了，

    co_master = folders.items['Master folder']
    co_child = folders.items['Child folder']
    print(co_master, co_child)

出现此错误：

    co = folders.items['Master folder']
TypeError: 'builtin_function_or_method' object is not subscriptable

我该怎么办？

Answer 1

您是要让path = sys.argv[1] all = glob.glob(path + "/x.txt") print all Output: ['/home/x1/sale/x.txt']等作为程序的输出，还是要将计数分配给变量？

在前一种情况下，您可以使用以下内容：

count_of_masterfolder = 1

在后一种情况下，以下将适用于您的特定情况：

for key, value in folder.items():
    print ("count of", key, "=", len(value))

Answer 2

您可以尝试 dict 理解：

{k: len(v) for k,v in folders.items()}

完整示例：

folders = {'Master folder': ['Training'], 'Child folder': [
    'Training videos', 'Training documents', 'Training workouts', 'Training practicals']}

print({k: len(v) for k,v in folders.items()})
# {'Master folder': 1, 'Child folder': 4}

Answer 3

folders = {'Master folder': ['Training'], 'Child folder': ['Training videos', 'Training documents', 'Training workouts', 'Training practicals']}

for key in list(folders.keys()):
  print(key, len(folders[key]))

>>>> Master folder 1
>>>>Child folder 4

EDIT: (to store outputs in list)

''''
mylist = []
for key in list(folders.keys()):
  print(key, len(folders[key]))
  mylist.extend(len(folders[key]))

Answer 4

为什么只需要使用len函数就可以解决问题

count_of_masterfolder = len(folders['Master folder'])
count_of_childfolder = len(folders['Child folder'])

如何使用关键字在python中从字典中计算项目值

4 个答案: