Python dict Usage

#字典的添加, delete, modify operations

Dict = {"A": "Apple", "B": "Banana", "G": "Grape", "O": "Orange"}

dict["W"] = "Watermelon"

Del (dict["a"])

Dict["g"] = "Grapefruit"

Print Dict.pop ("B")

Print Dict

Dict.clear ()

Print Dict

#字典的遍历

Dict = {"A": "Apple", "B": "Banana", "G": "Grape", "O": "Orange"}

For K in Dict:

Print "dict[%s] ="% k,dict[k]

Use of #字典items ()

Dict = {"A": "Apple", "B": "Banana", "C": "Grape", "D": "Orange"}

#每个元素是一个key和value组成的元组, output as a list

Print Dict.items ()

#调用items () Implementing a dictionary traversal

Dict = {"A": "Apple", "B": "Banana", "G": "Grape", "O": "Orange"}

For (K, V) in Dict.items ():

Print "dict[%s] ="% K, V

#调用iteritems () Implementing a dictionary traversal

Dict = {"A": "Apple", "B": "Banana", "C": "Grape", "D": "Orange"}

Print Dict.iteritems ()

For K, V in Dict.iteritems ():

Print "dict[%s] ="% K, V

For (K, v) in Zip (Dict.iterkeys (), Dict.itervalues ()):

Print "dict[%s] ="% K, V

#使用列表, dictionary as the value of the dictionary

Dict = {"A": ("apple",), "Bo": {"B": "Banana", "O": "Orange"}, "G": ["Grape", "Grapefruit"]}

Print dict["a"]

Print dict["a"][0]

Print dict["Bo"]

Print dict["Bo" ["O"]

Print dict["G"]

Print dict["G"][1]

Dict = {"A": "Apple", "B": "Banana", "C": "Grape", "D": "Orange"}

#输出key的列表

Print Dict.keys ()

#输出value的列表

Print dict.values ()

#每个元素是一个key和value组成的元组, output as a list

Print Dict.items ()

Dict = {"A": "Apple", "B": "Banana", "C": "Grape", "D": "Orange"}

it = Dict.iteritems ()

Print it

#字典中元素的获取方法

Dict = {"A": "Apple", "B": "Banana", "C": "Grape", "D": "Orange"}

Print Dict

Print Dict.get ("C", "Apple")

Print Dict.get ("E", "Apple")

Equivalent statement of #get ()

D = {"Key1": "Value1", "Key2": "Value2"}

If "Key1" in D:

Print d["Key1"]

Else

Print "None"

#字典的更新

Dict = {"A": "Apple", "B": "Banana"}

Print Dict

Dict2 = {"c": "Grape", "D": "Orange"}

Dict.update (DICT2)

Print Dict

Equivalent statement of #udpate ()

D = {"Key1": "Value1", "Key2": "Value2"}

E = {"Key3": "Value3", "Key4": "Value4"}

For K in E:

D[K] = E[k]

Print D

#字典E中含有字典D中的key

D = {"Key1": "Value1", "Key2": "Value2"}

E = {"Key2": "Value3", "Key4": "Value4"}

For K in E:

D[K] = E[k]

Print D

#设置默认值

Dict = {}

Dict.setdefault ("a")

Print Dict

Dict["a"] = "apple"

Dict.setdefault ("A", "default")

Print Dict

Sort #调用sorted ()

Dict = {"A": "Apple", "B": "Grape", "C": "Orange", "D": "Banana"}

Print Dict

#按照key排序

Print sorted (Dict.items (), Key=lambda d:d[0])

#按照value排序

Print sorted (Dict.items (), Key=lambda d:d[1])

#字典的浅拷贝

Dict = {"A": "Apple", "B": "Grape"}

Dict2 = {"c": "Orange", "D": "Banana"}

Dict2 = Dict.copy ()

Print Dict2

#字典的深拷贝

Import Copy

Dict = {"A": "Apple", "B": {"G": "Grape", "O": "Orange"}}

Dict2 = Copy.deepcopy (dict)

Dict3 = Copy.copy (dict)

dict2["B" ["g"] = "Orange"

Print Dict

dict3["B" ["g"] = "Orange"

Print Dict

This article is from the "My Ops Time" blog, so be sure to keep this source http://aaronsa.blog.51cto.com/5157083/1783324

Python dict Usage