python dictionary of dictionaries

Python dictionary, pythonThis article mainly introduces the dictionary in python, which is one of the most powerful data types in Python, this article explains what is a dictionary, how to create a

First, the contentIi. Exercise 1, Element classificationRequirements: A collection of the following values [11,22,33,44,55,66,77,88,99,90 ...], saving all values greater than 66 to the first key in the dictionary, and saving the value less than 66 to the value of the second key.That is: {' K1 ': All values greater than 66, ' K2 ': All values less than 66}L = [11,22,33,44,55,66,77,88,99,90]d = {' K1 ': [], ' K2 ': []}for i in Range (Len (l)): if l[i

1.Python dictionary (Dictionary)A dictionary is another mutable container model and can store any type of object.each key value of the dictionary (key=>value) pair with a colon (:) split, Each pair is separated by a comma (,) , and the entire

characters (including ' \ n ', ' \ R ', ' \ t ', '). Split split:names = ' Cao, Cjk,alex ' name2 = Names.split (', ') then name2 = [' Cao ', ' CJK ', ' Alex '] splits the string into lists as ', '. join The elements in the list into a string: Name3 = ' | '. Join (name2) Name3 = ' Cao|cjk|alex ' Determine if there are spaces: name = ' Cao Fa ', print (' in name ') return true str.format (): msg = ' Hello {name} ' it ' s been {time] days since I saw you ' MSG2 = Msg.format (name = ' C

Summary of several methods to traverse the python Dictionary (recommended) and python dictionary As follows: ADict = {'key1': 'value1', 'key2': 'value2', 'key3': 'value3'} print '----------- dict -----------' for d in aDict: print "% s: % s" % (d, aDict [d]) print '----------- item -----------' for (k, v) in aDict. ite

There are three built-in data structures in Python-lists, tuple tuples, and dictionary DictItems in the list are included in square brackets , and items are separated by commasTuples and lists are very similar, except that tuples and strings are immutable , meaning that you cannot modify tuples. Tuples are defined by a comma-separated list of items in parentheses .The most common use of tuples is in the pri

; shopping_list.count (' food ') #Statistics' food 'the number of elements, just added one, so now is2a>>> list2= [' Banana ', ' Apple '] #Create a new list>>> Shopping_list.extend (list2) #Merge the new list above into theshopping_listin>>> Shopping_list.sort () #sort the list>>> Shopping_list.reverse () #Invert the list>>> del Shopping_list[3:8] #Delete Index3to8the element, not including8>>> for I in Shopping_list: #Traverse List... print IThis article from the "Wind continue to blow" blog, d

Id_db={1: "WH", 2: "WX", 3:{1: "A", 2: "B", 3: "C"}, 4:["A", "B", "C"]}Print (id_db) #数据字典Print (id_db[2]) #取值id_db[3][1]= "AAAA" #改值 print (id_db)id_db[3][4]= "D" #增加元素 print (id_db)Del (id_db[3][4]) #删除指定元素 print (id_db)Id_db2={1: "Whhhhhh", 5: "555555"}Id_db.update (ID_DB2) #用一个字典更新另外一个字典 have a corresponding key update, no add print (id_db)Print (Id_db.keys ()) #打印所有KEYPrint (Id_db.values ()) #打印所有值Print (Id_db.setdefault (9, "DefaultValue")) #取得一个KEY下值如果没有则添加Print (id_db)For key in id_db: #

#-*-coding:utf-8-*-#1, DictionariesDict = {' name ': ' Zara ', ' age ': 7, ' class ': ' First '}#字典转为字符串, return: Print type (str (dict)), str (DICT)#字典可以转为元组, return: (' age ', ' name ', ' class ')Print tuple (dict)#字典可以转为元组, return: (7, ' Zara ', ' first ')Print tuple (dict.values ())#字典转为列表, return: [' age ', ' name ', ' class ']Print List (dict)#字典转为列表Print Dict.values#2, tuplestup= (1, 2, 3, 4, 5)#元组转为字符串, return: (1, 2, 3, 4, 5)Print tup.__str__ ()#元组转为列表, return: [1, 2, 3, 4, 5]Print List

;> a[1, 2, [3, 4]]>>> a.extend(b)>>> a[1, 2, [3, 4], 3, 4]InsertInsert (Index, object) inserts an element in the specified position before Index object>>> a = [0, 1, 2]>>> a.insert(1, 3)>>> a[0, 3, 1, 2]When modifying an element, use the subscript to determine which element is being modified before you can modify it.Demo #定义变量A，默认有3个元素 A = [‘xiaoWang‘,‘xiaoZhang‘,‘xiaoHua‘] print("-----修改之前，列表A的数据-----") for tempName in A: print(tempName) #修改元素 A[1] = ‘xiaoLu‘ print("-----修改之后，列表A的数据---

#-*-coding:utf-8-*-#1, DictionariesDict = {' name ': ' Zara ', ' age ': 7, ' class ': ' First '}#字典转为字符串, return: Print type (str (dict)), str (DICT)#字典可以转为元组, return: (' age ', ' name ', ' class ')Print tuple (dict)#字典可以转为元组, return: (7, ' Zara ', ' first ')Print tuple (dict.values ())#字典转为列表, return: [' age ', ' name ', ' class ']Print List (dict)#字典转为列表Print Dict.values#2, tuplestup= (1, 2, 3, 4, 5)#元组转为字符串, return: (1, 2, 3, 4, 5)Print tup.__str__ ()#元组转为列表, return: [1, 2, 3, 4, 5]Print List

Dictionaryinfo = { ' a ': 123, ' B ': ' xxx '}# value two methods the first one does not exist error # print (info["x"]) print (Info.get (' x ')) # delete del info[' a ']# Determine if key exists print (' a ' in info)Set/tupleImport Copy # introduces the Copy Library # Collection (array) names = [' AAA ', ' BBB ', ' CCC ', ' DDD ', [1, 2, 3, 4]]# insert Names.insert (0, ' first ') # Append NAMES.A Ppend (' last ') # Delete print (names) del Names[1]names.pop (1) names.remove ("ddd") # do

of times that STR appears in the mystr between start and endMystr=' Howmany fish is therein the pool'result_one=mystr.count ('A ', 1,10) result_two=mystr.count ('a')Print (str (result_one))print(str (result_two))Replace the str1 in mystr with the STR2 if count specifies that the replacement is not more than count times.Mystr=' Howmany fish is there in the pool ha ha'mystr.replace (' Ha','ha') mystr.replace ('ha') ,'Ha', 1)Slice mystr with Str as delimiter, if Maxsplit has a specified value,

Basic knowledge of the Python dictionary and basic knowledge of the python dictionary1. Add a key-Value Pair #! /Usr/bin/env pythoni1 = {'k1 ': 'cai', 'k2': 123} print (i1) i1 ['k3 '] = 0i1 ['k4'] = "rui" print (i1) ================================================================={ 'k1 ': 'cai ', 'k2': 123} {'k1': 'cai ', 'k2': 123, 'k3': 0, 'k4 ': 'rui '} 2. M

Python-Level 7 dictionary query and python dictionary Query 1 #-*-coding: UTF-8-*-2 3 4 # job requirements: 5 # five menus of municipalities, provinces, municipalities, counties, districts, and sub-streets; 6 # Step by step to all layers 7 # exit to the previous Layer 8 # exit program at any time 9 10 11 mapChina = {12

Python dictionary is a very important base type in Python, it is an efficient base type, not only used in writing programs, but even the implementation of Python's low-level use of a large number of dictionaries. Learn Python dictionarie