Python data type

Lesson Two

Today mostly speaks of data types

Divided into str string, int integer, dictionary, list, set, tuple

# ########################################## STR string ###############################################

#1, string first letter capital capitalize

# name = ' liuming '

# v = name.capitalize () #设置生成一个新的值

# print (name) #字符串本身不会变

# print (v) #新的值变化

# 2, string all uppercase to lowercase casefold

# name = ' liuming '

# v =name.casefold ()

# print (v)

#3, all uppercase lowercase

# name = "Liuming"

# V=name.lower ()

# print (v)

#4, set length, and center text

#参数1: Indicates medium length

#参数2: Fields that are filled in blanks (only 1 in length)

# name = ' liuming '

# v = name.center (15, '-')

# print (v)

#5, indicates the number of occurrences of the transfer value in the string

#参数1: The value to find (sub-sequence)

#参数2: Starting position (Index)

#参数3: End Position (index)

# name = ' Alexliumangnishausaisha '

# v = name.count (' a ')

# print (v)

# v = name.count (' li ', ') #起始位置

# print (v)

# v = name.count (' A ', 0,18) #结束位置

# print (v)

#6, whether to end with XX

# name = ' liuming '

# v = name.endswith (' ng ') #正确返回True, error returned false

# print (v)

#7, whether to start with XX

# name = ' liuming '

# v = name.startswith (' lb ') #正确返回True, error returned false

# print (v)

#8, convert into bytes

# name = ' Liu Mingchuan '

# V1 = Name.encode (encoding= ' utf-8 ') #指定编码

# v2 = Name.encode (encoding= ' GBK ') #指定编码

# Print (V1,V2)

#9, find the tab \ t to replace (including the beginning of the value), according to the tab, automatically generate the table (\ n line-break tab)

# name = ' Liu\tming\tal\nex\twu\tpei '

# v = name.expandtabs (#指定宽度)

# print (v)

#10, finds the index position of the specified subsequence: no return-1

# name = ' Liumingalex ' #不存在返回-1

# v = name.find (' q ')

# print (v)

# v = name.index (' o ') #不存在则报错

# print (v)

#11, string formatting

# i = ' My name:%s; age:%s; Gender:%s '

# v = i% (' Liu Mingchuan ', 19, ' Male ') #使用占位符格式化字符串

# print (v)

# i = ' My name: {0}; Age: {1}; Gender: {2} '

# v = I.format (' Liu Mingchuan ', 19, ' Male ') #使用format格式化字符串 (string position)

# print (v)

# i = ' My name: {name}; Age: {Ages}; Gender: {gender} '

# v = i.format_map ({' name ': ' Liu Mingchuan ', ' age ': +, ' gender ': ' That '}) #使用字典格式化字符串

# print (v)

#12, whether it is digital, Chinese characters

# name = ' alex8 Kanji '

# v =name.isalnum () #允许有数字

# print (v)

# v2 =name.isalpha () #不允许有数字

# Print (v2)

#13, judging whether it is a number

# num = ' ② 1232 '

# V1 = num.isdecimal () #可以识别 ' 123 '

# v2 = num.isdigit () #可以识别 ' 123 ', ' ② '

# v3 = num.isnumeric () #可以识别 ' 123 ', ' ② ', two

# Print (V1,V2,V3)

#14, whether it is an identifier

# n = ' name '

# v = n.isidentifier ()

# print (v)

#15是否全部是小写

# name = ' Lmslns '

# v =name.islower () #是否全部是小写

# print (v)

# v = name.isupper () #是否全部是大写

# print (v)

#16, all Caps

# name = ' liuming '

# v = name.upper () #字符串全部变大写, lower () all lowercase

# print (v)

#17, whether to include hidden xx

# name = ' two dog two dog two dog \nsbsbsbs '

# v = name.isprintable ()

# print (v)

#18, whether all are spaces

# name = ' '

# v =name.isspace ()

# print (v)

#19, element concatenation (element String) * * * * *

# name = ' Alex '

# v = ' _ '. Join (name) #指定拼接字符

# print (v)

# name_list = [' Alex ', ' liuming ', ' Liukang ')

# v = ' say '. Join (Name_list)

# print (v)

#20, left and right padding

#中center左rjust右ljust

# name = ' Alex '

# v =name.center (12, '-')

# print (v)

# v =name.rjust (12, ' * ')

# print (v)

# v =name.ljust (13, ' $ ')

# print (v)

#21, correspondence + translation

# m = Str.maketrans (' aeojj ', ' 12344 ') #对应关系

# name = "ASDKAHKJFHKJSH123HKJ;ASDSFJJJCNNN" #讲对应关系的字母翻译为数字

# v = name.translate (m)

# print (v)

#22, split preserving elements of a split

# name = ' Liu Mingchuan SB-li SB in '

# v = name.partition (' SB ')

# print (v)

#23, replace

# name = ' Liu Mingchuan SB-li SB in '

# v =name.replace (' SB ', ' hehe ') #把SB改成hehe

# print (v)

# v = name.replace (' SB ', ' heh ', 1) #把第一个SB改成heh

# print (v)

#24. Remove whitespace, \n\t, custom

# name = ' alex\t\n '

# v =name.strip ()

# print (v)

#25. Case conversion

# name = ' Alesx '

# v = name.swapcase ()

# print (v)

#26. Filling

# name = ' Alex '

# v = Name.zfill (#指定填充的个数)

# print (v)

#

# # #字符串总结

Name= ' liuming\t '

Name.capitalize () #字符串首字母大写

Name.casefold () #所有大写变小写

Name.lower () #所有大写变小写

Name.center #文本居中, 20 specify width,-Specify fill

Name.count (' u ', 1,6) #查找值, U is the value to find, 1 string position begins, 6 end of string

Name.startswith (' li ') #查询以xx开头

Name.endswith (' ng ') #查询以xx结尾

Name.expandtabs () #找到制表符 \ t to make a replacement table (containing the preceding values)

Name.format_map ({' name ': ' Alex '}) #字符串格式化, according to the dictionary

Name.format (' liuming ') #字符串格式化

Name.isalnum () #允许有数字

Name.isalpha () #不允许有数字

Name.isdecimal () #是否有数字可以识别123

Name.isdigit () #是否有数字可以识别123, ②

Name.isnumeric () #是否有数字可以识别123, two, ②

Name.isidentifier () #是否是标识符

Name.islower () #是否全部是小写

Name.isupper () #是否全部是大写

Name.upper () #全部变大写

Name.lower () #全部变小写

Name.isprintable () #是否包含隐藏的xx

Name.isspace () #是否全部是空格

' _ '. Join (name) #元素拼接

Name.rjust (A, '-') #左填充, 20 Specifies the width,-the filled thing

Name.ljust (A, '-') #右填充, 20 Specifies the width,-the filled thing

#对应关系 + Translation

m = Str.maketrans (' aeojj ', ' 12344 ') #对应关系

Name = "ASDKAHKJFHKJSH123HKJ;ASDSFJJJCNNN" #讲对应关系的字母翻译为数字

v = name.translate (m) #讲对应关系的字母翻译为数字

Name.partition (' um ') #分割, preserving the split elements according to the UM split

Name.replace (' um ', ' SB ', 1) #替换, um Replace with sb,1 specify location substitution

Name.strip () #移除空白 \t\n

Name.swapcase () #大小写转换

Name.zfill (20) #填充0, Width specified

Len (name) #测宽度

# ########################################## int integer ###############################################

#1. The binary representation of the current integer, the minimum number of digits

# age = 4 # 001

# Print (Age.bit_length ())

# #获取当前数据的字节表示

# age = 15

# v1 =age.to_bytes (10,byteorder= ' big ') #10进制, from right to left

# v2 =age.to_bytes (10,byteorder= ' little ') #10进制, from the left

# Print (V1,V2)

# ########################################## BOOL Boolean value ##########################################

# v = 0 #True

# v = ""-#空内容: False

# v = []--> #空内容: False

# ########################################## List ##########################################

#列表为可变类型

User_list = [' Liu Mingchuan ', ' Lee ', ' Gold ', ' Harry ', ' Li ']

#1. Append

# user_list.append (' Zhao Si ') #在最后追加赵四

# Print (user_list)

#2. Clear

# user_list.clear () #清空表格内容

# Print (user_list)

#3. Copy (Shallow copy)

# v = user_list.copy () #拷贝到v

# print (v)

# Print (user_list)

#4. Counting

# v = user_list.count (' li ') #计算列表中有几个李

# print (v)

# Print (user_list)

#5. Extending the original list

# user_list.extend ([' amount of protection ', ' Alex ']) #写新表扩展到之前表格里

# Print (user_list)

#6. Find an element index and cannot find an error

# v =user_list.index (' Li ')

# print (v)

#7. Delete and get the element index

# v =user_list.pop (1) #删除位置为1的值

# print (v)

# Print (user_list)

#8. deleting

# user_list.remove (' Lee ')

# Print (user_list)

#9. Flip (reverse)

# User_list.reverse ()

# Print (user_list)

#10. Sorting

# nums =[11,33,22,44,1,2]

# Nums.sort () #排序从小到大

# Print (nums)

# Nums.sort (reverse=true) #排序从大到小

# Print (nums)

###### Extra:

# user_list = [' Li Quan ', ' Liu Yi ', ' Li Quan ', ' Liu Kang ', ' peas ', ' dragons ']

# User_list[0]

# User_list[1:5:2] #索引

# del User_list[3] #删除

# for I in User_list:

# Print (i)

# User_list[1] = ' Ginger Day '

# user_list = [' Li Quan ', ' Liu Yi ', ' Li Quan ', ' Liu Kang ', ' peas ', [' Day ', ' Day ', ' Teddy '], ' little Dragons '

# li = [' Eric ', ' Alex ', ' Tony ']

#

# v = Len (li) #长度

# print (v)

#

# li.append (' seven ') #添加

# Print (LI)

#

# li.insert (0, ' Tony ') # Insertion

# Print (LI)

#

# Li[1] = ' Kelly ' #根据索引替换

#

# li.remove (' Eric ') #删除

# Print (list)

#

# v = li.pop (1) #删除并获取元素

# print (v)

# Print (LI)

#

# del li[2] #删除表

# del Li[0:2] # 0 =<x < 2

# Print (LI)

# li.reverse () #翻转

# Print (LI)

# for I in Li: #循环表

# Print (i)

# ######################################### Strong plug: range,enumrate #########################################

# 1. Please output 1-10

# 2.7: Generate all numbers now

# range (1,11) # Build 1-10

# 3.x: Will not be generated immediately, only one generation at a time of loop iteration

# for I in Range (1,11): #使用for循环生成1-10

# Print (i)

# for I in Range (1,11,2): # Generate 1-10,2 for not long build 1 3 5 7

# Print (i)

# for I in Range (10,0,-1): #

# Print (i)

# 1. 3.x will not be generated, after the iteration is created one after another;

"""

-2.7:

Range ()

Xrange () will not be generated, after the iteration is created one after another;

-3.x

Range () is not generated, and is created one after the iteration;

"""

# 2. Range: three parameter (+)

#

# li = [' Eric ', ' Alex ', ' Tony ']

# # Range,len,li Loop

# for I in range (0,len (LI)):

# ele = Li[i]

# Print (ele)

# li = [' Eric ', ' Alex ', ' Tony ']

# for I in Li:

# Print (i)

# for I in range (0,len (LI)):

# print (I+1,li[i])

# Enumerate generates an extra column of ordered numbers

# li = [' Eric ', ' Alex ', ' Tony ']

# for I,ele in Enumerate (li,1):

# Print (I,ele)

#

# v = input (' Please enter the product serial number: ')

# v = Int (v)

# item = Li[v-1]

# Print (item)

# ###### #列表总结

# user_list = [' Li Quan ', ' Liu Yi ', ' Liu Kang ', ' peas ', ' dragons ']

# user_list.append (' Liu I ') #追加

# user_list.clear () #清空表

# v =user_list.copy () #浅拷贝

# v =user_list.count (' Liu Yi ') #计数

# user_list.extend ([' Yes ', ' Aston ']) #扩展原列表

# v =user_list.index (' peas ') #查找索引, no error found

# v =user_list.pop (' 1 ') #删除并获取元素

# user_list.remove (' Dou Dou ') #删除

# user_list.reverse () #翻转

# User_list.sort () #排序从小到大

# User_list.sort (reverse=true) #排序从大到小

# User_list[1:5:2] #索引从1 -5,2 not often

# del user_list[2] #删除

# v= Len (user_list) #统计长度

# User_list.insert (1, ' Tony ') #插入

# ######################################### Dict: Dictionary: mutable type #########################################

# 1. Empty

# dic = {' K1 ': ' v1 ', ' K2 ': ' V2 '}

# dic.clear ()

# Print (DIC)

# 2. Shallow copy

# dic = {' K1 ': ' v1 ', ' K2 ': ' V2 '}

# v = dic.copy ()

# print (v)

# 3. Gets the specified value according to key; no error is present

# dic = {' K1 ': ' v1 ', ' K2 ': ' V2 '}

# v = dic.get (' k1111 ', 1111)

# print (v)

# v = dic[' k1111 ')

# print (v)

# 4. Delete and get the corresponding value value

# dic = {' K1 ': ' v1 ', ' K2 ': ' V2 '}

# v = dic.pop (' K1 ')

# Print (DIC)

# print (v)

# 5. Randomly deletes a key-value pair and gets the key value to delete

# dic = {' K1 ': ' v1 ', ' K2 ': ' V2 '}

# v = dic.popitem ()

# Print (DIC)

# print (v)

# k,v = Dic.popitem () # (' K2 ', ' v2 ')

# Print (DIC)

# Print (K,V)

# v = dic.popitem () # (' K2 ', ' v2 ')

# Print (DIC)

# print (v[0],v[1])

# 6. Add, do not operate if present

# dic = {' K1 ': ' v1 ', ' K2 ': ' V2 '}

# dic.setdefault (' K3 ', ' v3 ')

# Print (DIC)

# Dic.setdefault (' K1 ', ' 1111111 ')

# Print (DIC)

# 7. Bulk additions or modifications

# dic = {' K1 ': ' v1 ', ' K2 ': ' V2 '}

# dic.update ({' K3 ': ' V3 ', ' K1 ': ' V24 '})

# Print (DIC)

# dic = Dict.fromkeys ([' K1 ', ' K2 ', ' K3 '],123)

# Print (DIC)

# dic = Dict.fromkeys ([' K1 ', ' K2 ', ' K3 '],123)

# dic[' k1 ' = ' asdfjasldkf '

# Print (DIC)

# dic = Dict.fromkeys ([' K1 ', ' K2 ', ' K3 '],[1,])

# {

# k1:123123213, # [up]

# k2:123123213, # [1,]

# k3:123123213, # [1,]

# }

# dic[' K1 '].append (222)

# Print (DIC)

# ########## Extra:

#-Dictionaries can be nested

#-Dictionary key: Must be an immutable type

# dic = {

# ' K1 ': ' V1 ',

# ' K2 ': [All-in-all,],

#: ' Lllll ',

# 1: ' Fffffffff ',

# 111: ' Asdf ',

# }

# Print (DIC)

# key:

#-Non-changeable

#-true,1

# dic = {' K1 ': ' v1 '}

# del dic[' K1 ')

# Boolean value:

# 1 True

# 0 False

#

# bool (1111)

# # # # # #字典总结

DiC ={' K1 ': ' v1 ', ' K2 ': ' V2 '}

Dic.clear () #清空

V=dic.copy () #浅拷贝

V=dic.get (' keee ', 111) #根据key获取指定的value, there is no error

Dic.pop (' K1 ') #删除并获取删除的键值

Dic.setdefault (' K3 ', ' v3 ') #增加, do not operate if present

Dic.update ({' K3 ': ' V3 ', ' K4 ': ' v4 '}) #批量增加或修改

Del dic[' K1 '] #删除

# ##################################### set, set, non-repeating list; mutable type #####################################

# S1 = {"Alex", ' Eric ', ' Tony ', ' Li Quan ', ' Li Quan 11 '}

# s2 = {"Alex", ' Eric ', ' Tony ', ' Liu Yi '}

# exists in 1.s1, S2 does not exist

# v = s1.difference (S2)

# print (v)

# # # # # # # # # # # # # # # # # # S1, S2, then empty on S1, then re-copy

# s1.difference_update (S2)

# print (S1)

# exists in 2.s2, S1 does not exist

# v = s2.difference (S1)

# print (v)

# exists in 3.s2, S1 does not exist

# exists in S1, S2 does not exist

# v = s1.symmetric_difference (S2)

# print (v)

# 4. Intersection

# v = s1.intersection (S2)

# print (v)

# 5. and set

# v = s1.union (S2)

# print (v)

# 6. Removed from

# S1 = {"Alex", ' Eric ', ' Tony ', ' Li Quan ', ' Li Quan 11 '}

# S1.discard (' Alex ')

# print (S1)

# S1 = {"Alex", ' Eric ', ' Tony ', ' Li Quan ', ' Li Quan 11 '}

# s1.update ({' Alex ', ' 123123 ', ' FFF '})

# print (S1)

# ##### Extra:

# S1 = {"Alex", ' Eric ', ' Tony ', ' Li Quan ', ' Li Quan 11 '}

# for I in S1:

# Print (i)

# S1 = {"Alex", ' Eric ', ' Tony ', ' Li Quan ', ' Li Quan 11 ', (11,22,33)}

# for I in S1:

# Print (i)

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Python data type