如何在python字典中为每个键添加多个值
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How to add multiple values per key in python dictionary
提问by jsnabs2
My program needs to output a list of names with three numbers corresponding to each name however I don't know how to code this is there a way I could do it as a dictionary such as cat1 = {"james":6, "bob":3}but with three values for each key?
我的程序需要输出一个名称列表，其中包含与每个名称对应的三个数字，但是我不知道如何编码，有没有一种方法可以将其作为字典来实现，例如cat1 = {"james":6, "bob":3}每个键具有三个值？
采纳答案by Alex
The value for each key can either be a set (distinct list of unordered elements)
每个键的值可以是一个集合（无序元素的不同列表）
cat1 = {"james":{1,2,3}, "bob":{3,4,5}}
for x in cat1['james']:
print x
or a list (ordered sequence of elements )
或列表（元素的有序序列）
cat1 = {"james":[1,2,3], "bob":[3,4,5]}
for x in cat1['james']:
print x
回答by Dr Xorile
Both answers are fine. @santosh.ankr used a dictionary of lists. @Jaco de Groot used a dictionary of sets (which means you cannot have repeated elements).
两个答案都很好。@santosh.ankr 使用了一个列表字典。@Jaco de Groot 使用了一个集合字典（这意味着你不能有重复的元素）。
Something that is sometimes useful if you're using a dictionary of lists (or other things) is a default dictionary.
如果您使用列表（或其他东西）的字典，有时会有用的东西是默认字典。
With this you can append to items in your dictionary even if they haven't been instantiated:
有了这个，即使它们尚未实例化，您也可以附加到字典中的项目：
>>> from collections import defaultdict
>>> cat1 = defaultdict(list)
>>> cat1['james'].append(3) #would not normally work
>>> cat1['james'].append(2)
>>> cat1['bob'].append(3) #would not normally work
>>> cat1['bob'].append(4)
>>> cat1['bob'].append(5)
>>> cat1['james'].append(5)
>>> cat1
defaultdict(<type 'list'>, {'james': [3, 2, 5], 'bob': [3, 4, 5]})
>>>
回答by Ahmed tiger
the key name and values to every key:
每个键的键名和值：
student = {'name' : {"Ahmed " , "Ali " , "Moahmed "} , 'age' : {10 , 20 , 50} }
for keysName in student:
print(keysName)
if keysName == 'name' :
for value in student[str(keysName)]:
print("Hi , " + str(value))
else:
for value in student[str(keysName)]:
print("the age : " + str(value))
And the output :
和输出：
name
Hi , Ahmed
Hi , Ali
Hi , Moahmed
age
the age : 50
the age : 10
the age : 20
