Master Python Lists: From Basics to Advanced Operations

Hello everyone, I'm Cai, and today I'll share knowledge about Python lists

1. List Syntax

Example: namesList = ['xiaoWang','xiaoZhg','xiaa'] Unlike C arrays, Python lists can hold elements of different types.

testList = [1, 'a']

2. List Operations (Add, Delete, Modify, Search)

1) Adding elements

Use append() to add an element.

# Define list A with three elements
A = ['rr', 'rag', 'rte']
print("-----Before adding, list A-----")
for tempName in A:
    print(tempName)
temp = input('Please enter a student name to add:')
A.append(temp)
print("-----After adding, list A-----")
for tempName in A:
    print(tempName)

Result:

2) Modifying elements

Use index to specify which element to change.

# Define list A
A = ['rr', 'rag', 'rte']
print("-----Before modification, list A-----")
for tempName in A:
    print(tempName)
A[1] = 'Lu'
print("-----After modification, list A-----")
for tempName in A:
    print(tempName)

Result:

3) Searching elements

Common methods: in, not in, index, count. in: returns True if element exists. not in: returns True if element does not exist.

# List to search
A = ['rr', 'rag', 'rte']
findName = input('Enter the name to search:')
if findName in A:
    print('Found the content in the list')
else:
    print('Not found')

Result (found):

Result (not found):

4) Deleting elements

del

removes by index.

Name = ['加勒比海盗','骇客帝国','第一滴血','霍比特人','速度与激情']
print('------Before deletion------')
for tempName in Name:
    print(tempName)
del Name[2]
print('------After deletion------')
for tempName in Name:
    print(tempName)

Result:

pop

removes the last element.

Subject = ['数学','语文','英语','地理','历史']
print('------Before deletion------')
for tempSubject in Subject:
    print(tempSubject)
del Subject[2]  # delete second element
print('------After deletion------')
for tempSubject in Subject:
    print(tempSubject)

Result:

remove

deletes by value.

Subject = ['数学','语文','英语','地理','历史']
print('------Before deletion------')
for tempSubject in Subject:
    print(tempSubject)
Subject.remove('英语')
print('------After deletion------')
for tempSubject in Subject:
    print(tempSubject)

Result:

5) Sorting

sort()

orders the list (default ascending). Use reverse=True for descending. reverse() reverses the list.

a = [1,4,2,3]
print(a)
a.reverse()
print(a)  # reversed
a.sort()
print(a)  # sorted ascending
a.sort(reverse=True)
print(a)  # sorted descending

Result:

3. Nested Lists

1) List nesting

Lists can contain other lists.

Letter = [['A','B'], ['C','D','E'], ['F','R']]

2) List of dictionaries

Example: roster.

pep1 = {'name':'蔡同学','school':'北京大学'}
pep2 = {'name':'陈作同','school':'中山大学'}
pep_list = [pep1, pep2]
for pepo in pep_list:
    print(pepo)

Result:

3) Dictionary with list values

Example: book tags.

book = {'title':'现代艺术150年','tags':['数学','历史学']}
for tags in book['tags']:
    print(tags)

Result:

4. Summary

This article explains Python list fundamentals, common operations, and typical issues with solutions, helping readers better understand list usage.