if not a:
    print("List is empty")

Using the implicit booleanness of the empty list is quite Pythonic.

Answer from Patrick on Stack Overflow
🌐
Stack Overflow
stackoverflow.com › questions › 53513 › how-do-i-check-if-a-list-is-empty
python - How do I check if a list is empty? - Stack Overflow
Top answer
1 of 16
7312
if not a:
    print("List is empty")

Using the implicit booleanness of the empty list is quite Pythonic.

2 of 16
1556

The Pythonic way to do it is from the PEP 8 style guide.

For sequences, (strings, lists, tuples), use the fact that empty sequences are false:

# Correct:
if not seq:
if seq:

# Wrong:
if len(seq):
if not len(seq):
🌐
GeeksforGeeks
geeksforgeeks.org › python › python-check-if-list-empty-not
Check if a list is empty or not in Python - GeeksforGeeks
October 24, 2024 - If there were items in the list, not a would be False. ... We can also use len() function to see if a list is empty by checking if its length is zero. ... Explanation: len(a) returns 0 for an empty list.
Videos
06:42
🌐 YouTube
How To Check If A List Is Empty In Python - YouTube
September 29, 2021
551
🌐 youtube.com
Checking for an empty list in Python
05:43
🌐 YouTube
Python Program #54 - Check If a List is Empty in Python - YouTube
June 23, 2023
10:26
🌐 YouTube
5 Ways to Check if a List is Empty in Python (TUTORIAL) - YouTube
June 27, 2020
01:10
🌐 YouTube
How to check Python List is Empty | Ways to check Python List is ...
June 3, 2024
05:28
🌐 YouTube
How to Check if a List is Empty in Python | Python Lists - YouTube
September 1, 2022
5.08K
View all
View all
🌐
Built In
builtin.com › articles › python-check-if-list-is-empty
Python Check if a List Is Empty: A Guide | Built In
In this context, lists are considered truthy if they are non-empty, meaning that at least one argument was passed to the list. So, if you want to check if a list is empty, you can simply use the not operator.
🌐
Flexiple
flexiple.com › python › check-if-list-is-empty-python
Python isEmpty() equivalent – How to Check if a List is Empty in Python - Flexiple - Flexiple
To check if a list is empty in Python using the not operator, simply evaluate the list in a conditional statement. If the list is empty, the condition not my_list returns True.
🌐
freeCodeCamp
freecodecamp.org › news › how-to-check-if-a-list-is-empty-in-python
Python isEmpty() equivalent – How to Check if a List is Empty in Python
April 19, 2023 - people_list = [] if people_list == []: print("Your list is empty") else: print("Your list is not empty") # Your list is empty · In the example above, we compared the people_list list to an empty list: if people_list == [] You can play around ...
🌐
Reddit
reddit.com › r/learnpython › how do i check if this list is "empty"?
r/learnpython on Reddit: How do I check if this list is "empty"?
December 8, 2022 -

I'm completely stumped on a computer science assignment because our lecturer has given us zero information. We're supposed to have the user input a list and check if the list is in decreasing order and print a suitable message if it is. That part works fine. However, if the list is "empty" (I'll explain the quotations in a second) then it should print the list is empty.

The problem is that, according to our brief we're supposed to use .split(",") in order to allow the user to separate their numbers with commas. The problem lies in the fact that even if a user hits enter without inputting anything, the list is still '1' long with just an empty string. I've been scouring the web to find out how to check if a list is empty. But all the tutorials have so far just been in relation to actually empty lists (as in, list = []). One did use the all() function to check that all items in the list were strings, which did work and let me print that the list is empty, but broke the original function. Could someone please help me I'm tearing my hair out with this.

--

def checkOrder():

# checks, etc.

integer_list = []

listLength = len(integer_list)

increasing = 0

decreasing = 0

singleValue = 0

# Converting inputted numbers into a split list

userInput = input("Please enter your numbers seperated by a comma (,):")

inputtedStrings = userInput.split(",")

for number in inputtedStrings:

inputtedIntegers = int(number)

integer_list.append(inputtedIntegers)

# Enumerating list

for i, val in enumerate(integer_list[:-1]):

if val <= integer_list[i+1]:

increasing = 1

elif val >= integer_list[i+1]:

decreasing = 1

# Check for a single value

if len(integer_list) == 1:

singleValue = 1

if len(integer_list) == 1 and

print("The list is empty.")

if increasing == 1:

print("The numbers are in increasing order.")

elif decreasing == 1 or singleValue == 1:

print("The numbers are in decreasing order.")

checkOrder()

--

Top answer
1 of 5
8
Well there are a few ways you could deal with this. First would be to check if userInput is an empty string before converting it to a list. Another possibility would be to filter the list to remove all empty strings, eg via a list comprehension. Or you could do the filtering inside the loop you already have that converts to integers. Or, again inside that loop, you could use a counter variable to keep track of how many integers you've converted, and print an error afterwards if it's 0. And so on. The main thing here is that you should get away from thinking about how to code something, but first work out what the steps should be, and only then code it.
2 of 5
3
arr = [''] print(any(arr)) # False any and all are pretty useful built-in functions for iterative boolean checks.
🌐
Better Stack
betterstack.com › community › questions › how-to-check-if-list-is-empty-in-python
How do I check if a list is empty in Python? | Better Stack Community
You can check if a list is empty by using the len() function to check the length of the list.
🌐
Python Morsels
pythonmorsels.com › checking-for-an-empty-list-in-python
Checking for an empty list in Python - Python Morsels
August 20, 2024 - So instead of asking whether an object is equal to an empty list, many Python programmers prefer to check for the behavior of emptiness via a falsiness check: >>> if not numbers: ... print("The collection is empty.") ...
Find elsewhere
🌐
Vultr
docs.vultr.com › python › examples › check-if-a-list-is-empty
Python Program to Check If a List is Empty | Vultr Docs
December 6, 2024 - my_list = [] if len(my_list) == 0: print("List is empty.") else: print("List is not empty.") Explain Code · The len(my_list) == 0 condition will be True if my_list is empty, triggering the print statement.
🌐
TutorialsPoint
tutorialspoint.com › how-to-check-if-a-list-is-empty-in-python
How to check if a list is empty in Python?
Print "Empty list", if the condition is true. The following program checks whether the input list is empty or not using the empty list[] literal -
🌐
Python Engineer
python-engineer.com › posts › check-if-list-is-empty
How to check if a List is empty in Python - Python Engineer
Although the first approach is considered to be more Pythonic, some people prefer the explicit second approach. Note that the official PEP 8 Python Style Guide recommends the first way: "For sequences, (strings, lists, tuples), use the fact that empty sequences are false" # Correct: if not seq: if seq: # Wrong: if len(seq): if not len(seq):
🌐
PythonHow
pythonhow.com › how › check-if-a-list-is-empty
Here is how to check if a list is empty in Python
# Define a list my_list = [] # Check if the list is empty if not bool(my_list): print("The list is empty.") else: print("The list is not empty.")This will also print 'The list is empty'.
🌐
Codedamn
codedamn.com › news › python
Python List Is Empty: All Methods to Check
July 1, 2023 - A: No, Python does not have a built-in function specifically to check if a list is empty.
🌐
Medium
pavolkutaj.medium.com › how-to-check-if-a-list-dict-or-set-is-empty-in-python-as-per-pep8-35d8c64d07d0
How to Check if a List, Dict or Set is Empty in Python as per PEP8 | by Pavol Z. Kutaj | Medium
September 7, 2023 - duck typing means relying on general/conventional interfaces → rather than explicitly checking for types → you could argue that conventional interfaces are not magical, right · so something like if a == [] is forcing a particular type (() ...
🌐
Spark By {Examples}
sparkbyexamples.com › home › python › check if the list is empty in python
Check if the List is Empty in Python - Spark By {Examples}
May 31, 2024 - # Empty List if not list2: print("List 2 Empty") # Output: # List 2 Empty · In Python, the empty list is considered as False hence to check if the list is empty, pass the list as an argument to the bool(). if the list doesn’t have any elements ...
🌐
Stack Abuse
stackabuse.com › how-to-check-if-list-is-empty-in-python
How to Check if List is Empty in Python
February 20, 2023 - Although this method looks simple, ... those who are new to python or coding itself usually consider it more intuitive: if len(py_list) == 0: print('List is empty') else: print('List not empty')...
🌐
Sentry
sentry.io › sentry answers › python › check if a list is empty in python
Check if a list is empty in Python | Sentry
The Python style guide, PEP-8, recommends checking whether a list (or other sequence) is False to determine that it is empty. For example: ... Tasty treats for web developers brought to you by Sentry. Get tips and tricks from Wes Bos and Scott Tolinski.SEE EPISODES · Considered “not bad” by 4 million developers and more than 150,000 organizations worldwide, Sentry provides code-level observability to many of the world’s best-known companies like Disney, Peloton, Cloudflare, Eventbrite, Slack, Supercell, and Rockstar Games.
🌐
Enterprise DNA
blog.enterprisedna.co › python-check-if-list-is-empty-7-methods-explained
Python: Check If List is Empty (7 Methods Explained) – Master Data Skills + AI
To determine if a list is empty in Python, you can use the not operator. This method takes advantage of the implicit boolean value of an empty list. When you use not with an empty list, it returns True. ... The best way to check if a list has elements is to use the len() function.
🌐
The Renegade Coder
therenegadecoder.com › code › how-to-check-if-a-list-is-empty-in-python
How to Check if a List is Empty in Python: Type Flexibility and More – The Renegade Coder
May 21, 2024 - As always, in this section, we do a little recap of the solutions we’ve shared above: my_list = list() # Check if a list is empty by its length if len(my_list) == 0: pass # the list is empty # Check if a list is empty by direct comparison ...
🌐
w3resource
w3resource.com › python-exercises › list › python-data-type-list-exercise-8.php
Python: Check a list is empty or not - w3resource
# Create an empty list 'l' l = [] # Check if the list 'l' is empty using the 'not' keyword if not l: # If the list is empty, print the message "List is empty" print("List is empty")