04. basic data type - list, tuple

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One 、 list

1.1 List introduction

       列 Table is python The basic data type of ⼀, Other programming languages ⾔ There are similar data types . such as JS In the array , java Arrays in etc . It is a [ ] Cover up , Every element ⽤’ , ' Separate and store all kinds of data types :

   list = [1, ' ha-ha ', " Woo hoo ", [1,8,0," Baidu "], (" I "," It's called ", " element ", " Group "), "abc", {
    " My name is ":"dict Dictionaries "},{
    " I'm the assembly "," aggregate "}]

        Lists are compared to characters 串. Not only can different types of data be stored , And it can be stored and enlarged 量 The data of .32 position python It can store : 536870912 Elements , 64 It can store : 1152921504606846975 Elements . And the list is ordered ( In the order you save ), There is an index , Can cut ⽚⽅便 Value .

2.2 列 Indexing and slicing of tables

列 Tables, like strings, have indexes :

list = [" Gentiana ", " still 林", "⻢ Yun ", " Doctor Zhou Hong ", " Xiang Huaqiang "]
print(list[0]) #  For the first ⼀ Elements 
print(list[1]) #  For the first ⼀ Elements 
print(list[2]) #  For the first ⼀ Elements 
list[3] = " Strong mobility " #  Be careful .  Column 列 Tables can be sent ⽣ Make a difference .  this ⾥ in 里 And string 串 Dissimilarity 
print(list) # [' Gentiana ', ' Wang Jianlin ', '⻢ Yun ', ' Strong mobility ', ' Xiang Huaqiang ']
s0 = " Xiang Huaqiang "
s0[1] = " beautiful " # TypeError: 'str' object does not support item assignment  The value in the string cannot be changed 
print(s0)

Slice of the list :

list = [" Gentiana ", " still 林", "⻢ Yun ", " Doctor Zhou Hong ", " Xiang Huaqiang "]
print(list[0:3]) # [' Gentiana ', ' still 林', '⻢ Yun ']
print(list[:3]) # [' Gentiana ', ' still 林', '⻢ Yun ']
print(list[1::2]) # [' still 林', ' Doctor Zhou Hong ']  There are steps ⻓
print(list[2::-1]) # ['⻢ Yun ', ' still 林', ' Gentiana ']  You can also take it backwards 
print(list[-1:-3:-2]) #  Step backwards ⻓

Two 、 Add, delete, modify and search the list

1. increase    Be careful ： list and str It is not ⼀ What kind of ,list Can send ⽣ Change , So go straight to the original object ⾏了 operation .

Increase method	detailed
append()	Add elements at the end of the list
insert()	Insert the element at the index position of the specific list , The following elements are automatically moved back
extend()	The specified list element （ Or any iteratable element ） Add to the end of the current list

list = [" Gentiana ", "林 Junjie ", " Chow yun-fat ", " Zhou Zhiruo "]
print(list) # [' Gentiana ', '林 Junjie ', ' Chow yun-fat ', ' Zhou Zhiruo ']
list.append("wusir")
print(list) # [' Gentiana ', '林 Junjie ', ' Chow yun-fat ', ' Zhou Zhiruo ', 'wusir']

list = []
while True:
	content = input(" Please enter your record ⼊ I'm a member of the team ⼯ Information ,  Input Q sign out :")
	if content.upper() == 'Q':
		break
	list.append(content)
print(list)

list = [" Gentiana ", " Zhangdezhong ", " Kondefu "]
list.insert(1, " Lau Andy ") #  stay 1 The position of the plug ⼊ Lau Andy .  The original element moves back ⼀ a 
print(list) # [' Gentiana ', ' Lau Andy ', ' Zhangdezhong ', ' Kondefu ']

#  Add... Iteratively 
list = [" Wang Zhiwen ", " Zhang ⼀ mountain ", " Boundless sea of pain "]
list.extend([" Gentiana ", " Hemp flowers 不 Pain, "])
print(list) # [' Wang Zhiwen ', ' Zhang ⼀ mountain ', ' Boundless sea of pain ', ' Gentiana ', ' Hemp flowers 不 Pain, ']

2. Delete

Delete method	detailed
pop()	Delete the element at the index position corresponding to the list , Delete the last... By default
remove()	Delete the first specified element in the list
clear()	clear list
del	Delete list elements as index subscripts

list = [" Gentiana ", " still 林", " Li Jiacheng ", " Wang Fugui "]
print(list)
deleted = list.pop() #  Delete the last one 
print(" The deleted ", deleted) #  The deleted wangfugui 
print(list) # [" Gentiana ", " still 林", " Li Jiacheng "]

el = list.pop(2) #  Delete 2 Element number 
print(el) #  Li Jiacheng 
print(list) # [" Gentiana ", " still 林"]

list.remove(" Gentiana ") #  Deletes the specified element 
print(list) # [" still 林"]
# list.remove(" ha-ha ") #  Deleting nonexistent elements will result in an error 
# print(list)

#  Empty list
list.clear() 
print(list) # []

#  Slice delete 
list = [" Gentiana ", " still 林", " Li Jiacheng ", " Wang Fugui "]
del list[0:3]
print(list) # [' Wang Fugui ']  Go to the head but not the tail 

3. modify

Modification method	detailed
Index modification	Select the list elements by index and re assign values
Slice modification	Select multiple elements of the list by slicing to re assign values

#  modify 
list = [" The white ", " It's too dark ", " Five colors ", " King of silver ", " Day day "]
list[1] = " Too dirty " #  hold 1 The number element has been modified to be too dirty 
print(list) # [" The white ", " Too dirty ", " Five colors ", " King of silver ", " Day day "]

list[1:4:3] = [" Gentiana ", " tencent "] #  cut ⽚ Modification is also OK.  If the step length is not 1,  it is to be noted that .  Number of elements 
print(list) # ValueError: attempt to assign sequence of size 2 to extended slice of size 1

list[1:4:2] = [" Gentiana ", " tencent "] 
print(list) # [' The white ', ' Gentiana ', ' Five colors ', ' tencent ', ' Day day ']

list[1:4] = [" Li Jiacheng "] #  If cut ⽚ No step ⻓ Or step ⻓ yes 1.  No ⽤ Turn off ⼼ Number 
print(list) # [' The white ', ' Li Jiacheng ', ' Day day ']

4. Inquire about

Query methods	detailed
for loop	列 Table is ⼀ Iteratable objects , So you can go in 行 for Mix and match if Judge , Filter query
in	Returns if a value is found in the specified sequence True, Otherwise return to False

list = [" too ⽩", " It's too dark ", " Five colors ", " King of silver ", "⽇ God "]
for i in list:
	if i == ' King of silver ':
		print(i)
		break
else:
	print(" I didn't find ")

print(" King of silver " in list)

5. Other operating

Other operating	detailed
count()	Count the number of elements in a list
sort()	Sort the elements in the list in ascending order
reverse()	Negate the elements in the list
len()	Find the number of all elements in the list

list = [" The white ", " It's too dark ", " Five colors ", " King of silver ", "⽇ God ", " too ⽩"]
c = list.count(" too ⽩") #  The query is too ⽩ Number of occurrences 
print(c)

list = [1, 11, 22, 2]
list.sort() #  Sort .  Default ascending order 
print(list)
list.sort(reverse=True) #  Descending 
print(list)

list = [" too ⽩", " too ⿊", " 5、 ... and ⾊", " King of silver ", "⽇ God ", " too ⽩"]
print(list)
list.reverse()
print(list)

l = len(list) #  List ⻓ degree 
print(l)

3、 ... and 、 Nesting of lists

Use dimension reduction operation , Just look at it layer by layer

list = [1, " too ⽩", "wusir", ["⻢⻁ Pain, ", [" Coca Cola "], " Wang Jianlin "]]

#  find  wusir
print(list[2])

#  Find too ⽩ and wusir
print(list[1:3])

#  Find too ⽩ Of ⽩ word 
print(list[1][1])

#  take wusir Get .  then ⾸ word ⺟⼤ Write .  Throw it back 
s = list[2]
s = s.capitalize()
list[2] = s
print(list)

#  Abbreviation 
list[2] = list[2].capitalize()
print(list)

#  Put too ⽩ Change to too ⿊
list[1] = list[1].replace("⽩", "⿊")
print(list)

#  hold ⻢⻁ Change the pain into ⻢ Relieve pain 
list[3][0] = list[3][0].replace("⻁", " turn ")
print(list[3][0])


#  Add sprite to the list of Coca Cola 
list[3][1].append(" Sprite ")
print(list)

Four 、 Tuples and tuples nesting

Tuples : Commonly known as immutable list .⼜ Be made a read-only list , Tuples are also python The basic data type of ⼀, ⽤⼩ Enclosed in brackets , 里⾯ You can put any kind of data , Queries can be 、 The cycle can also 、 Slices can also be 、 But it can't be changed （ increase 、 Delete ）.

tu = (1, " too ⽩", " Li ⽩", " too ⿊", " Yes? ⿊")
print(tu)
print(tu[0])
print(tu[2])
print(tu[2:5]) #  After slicing, it's still tuple 

# for Cycle through the epoch group 
for el in tu:
	print(el)
	
#  Try to modify tuples 
# tu[1] = " Careless pain " #  Report errors  'tuple' object does not support item assignment

tu = (1, " ha-ha ", [], " ha-ha ")
# tu[2] = ["fdsaf"] #  This change is not ⾏

tu[2].append(" Gentiana ") #  It can be changed .  No mistake 
tu[2].append(" Wang Jianlin ")
print(tu)  #(1, ' ha-ha ', [' Gentiana ', ' Wang Jianlin '], ' ha-ha ')

About immutability , Be careful : this 里 The immutability of tuples means that the child elements are immutable , And inside the child element ⼦ Elements can be changed , It depends. ⼦ Whether the element is a mutable object

If there is only ⼀ Elements . ⼀ Be sure to add ⼀ Commas , Otherwise it's not a tuple

tu = (1,)
print(type(tu))

Tuples also have count(), index(), len() Other methods . You can test it yourself

5、 ... and 、 range

range It can help us get a set of data . adopt for The loop can get these data

for num in range(10):
	print(num)
	
for num in range(1, 10, 2):
	print(num)
	
for num in range(10, 1, -2): #  On the contrary ,  He Che ⽚ slice ⼀ equally 
	print(num)

Review questions

1. What does a list do ？
2. How to get the elements in the list ？
3. What are the ways to add elements to the list ？ What's the difference between them ？
4. How to delete the elements of the list ？ What's the difference between them ？
5. How to modify the elements in the list ？ What's the difference between them ？
6. What are the methods to query the elements in the list ？ What's the difference between them ？
7. How to count the number of elements in a list ？
8. How to sort the elements in the list in ascending order ？
9. How to negate elements in a list ？
10. How to find the number of all elements in the list ？
11. Encountered multi nested list , How to operate on list elements ？
12. Tuples vs. lists , What are the characteristics of each ？
13. range What does the function do ？ What is the method of use ？