You can append the elements of one list to another with the "+=" operator. Note that the "+" operator creates a new list.
a = [1, 2, 3]
b = [10, 20]
a = a + b # Create a new list a+b and assign back to a.
print a
# [1, 2, 3, 10, 20]
# Equivalently:
a = [1, 2, 3]
b = [10, 20]
a += b
print a
# [1, 2, 3, 10, 20]
If you want to append the lists and keep them as lists, then try:
result = []
result.append(a)
result.append(b)
print result
# [[1, 2, 3], [10, 20]]
DigitalOcean
digitalocean.com › community › tutorials › python-add-to-array
Python Array Add: How to Append, Extend & Insert Elements | DigitalOcean
April 15, 2025 - Learn how to add elements to an array in Python using append(), extend(), insert(), and NumPy functions. Compare performance and avoid common errors.
Built In
builtin.com › software-engineering-perspectives › append-python
Python List Append() - How to Append Lists in Python | Built In
Our list index starts with 0 and ends with 5, which we can check using the pre-built len() function: ... The append() method in Python adds a single item to the end of the existing list.
Python appending array to an array - Stack Overflow
I am currently working on DES implementation.In one part of the code I have to append array to an array.Below is my code: C0=[1, 1, 1, 1, 0, 0, 0, 0, 1, 1, 0, 0, 1, 1, 0, 0, 1, 0, 1, 0, 1, 0, 1,... More on stackoverflow.com
How do I append a value to an array in Python? - Stack Overflow
For a numerical analysis class I need to make a for loop that must do a couple of things: Make a certain 'Dt' (a time step that gets smaller and smaller) and add this to an array called Dt_list. T... More on stackoverflow.com
Append and write to an array?
x.append() will modify the list, I don't understand what you mean by "code itseld is unaffected" More on reddit.com
7
1
September 28, 2022numpy.append() in Python --- slower (faster) than appending to a List ?
That's right. A numpy array is a real array in a computer science sense, which means it cannot be resized. Since appending requires resizing, numpy is forced to create a whole new array with a bigger allocation and copy all the old data over before adding any new data. This takes a lot of time. Python lists are resizeable therefore appending is very fast. More on reddit.com
2
0
July 7, 2020Videos
append Method in Python| HOW TO USE append() function in PYTHON| ...
03:42
✅ How To Append An Array To An Array In Python 🔴 - YouTube
00:51
Append to an array in Python #100daysofcode #python - YouTube
python append object to array
00:14
How Do You Append To An Array in Python? [GCSE COMPUTER SCIENCE] ...
Python Programming: appending an array and summing its ...
Tutorialspoint
tutorialspoint.com › home › python › python array append method
Python Array Append Method
February 21, 2009 - This method accepts the element that has to be appended. This method does not return any value. The following is the basic example of the Python Array append() method −
Vercaa
vercaa.com › index.php
Adding Array Items in Python: Appending Elements to Arrays - Vercaa Hosting
The extend() method in array class appends all the elements from another array of same typecode. ... import array as arr a = arr.array('i', [1, 2, 3, 4, 5]) b = arr.array('i', [6,7,8,9,10]) a.extend(b) print (a) ... array('i', [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]) The End! should you have any inquiries, ...
freeCodeCamp
freecodecamp.org › news › append-in-python-how-to-append-to-a-list-or-an-array
Append in Python – How to Append to a List or an Array
January 7, 2022 - In this article, you'll learn about the .append() method in Python. You'll also see how .append() differs from other methods used to add elements to lists. Let's get started! What are lists in Python? A definition for beginners An array in programmi...
TutorialsPoint
tutorialspoint.com › python-program-to-append-an-element-into-an-array
Python Program to Append an Element Into an Array
The element 9 is appended to the array, and which is added at the end of the array. The array module in Python allows us to create an array, and that can compactly represent an array.
W3Schools
w3schools.com › python › gloss_python_array_add.asp
Python Add Array Item
Python Examples Python Compiler ... Q&A Python Bootcamp Python Certificate Python Training ... You can use the append() method to add an element to an array....
Spark By {Examples}
sparkbyexamples.com › home › python › how to append numpy arrays examples
How to Append NumPy Arrays Examples - Spark By {Examples}
March 27, 2024 - numpy.append() is used to append two or multiple arrays at the end of the specified NumPy array. The NumPy append() function is a built-in function in the NumPy package of Python.
Top answer 1 of 4
149
You can append the elements of one list to another with the "+=" operator. Note that the "+" operator creates a new list.
a = [1, 2, 3]
b = [10, 20]
a = a + b # Create a new list a+b and assign back to a.
print a
# [1, 2, 3, 10, 20]
# Equivalently:
a = [1, 2, 3]
b = [10, 20]
a += b
print a
# [1, 2, 3, 10, 20]
If you want to append the lists and keep them as lists, then try:
result = []
result.append(a)
result.append(b)
print result
# [[1, 2, 3], [10, 20]]
2 of 4
61
Apart from + operator there's another way to do the same i.e. extend()
a = [1, 2, 3]
b = [10, 20]
a.append(b) # Output: [1, 2, 3, [10, 20]]
a.extend(b) # Output: [1, 2, 3, 10, 20]
You can use these 2 functions for manipulating a list as per your requirement.
Vultr Docs
docs.vultr.com › python › third-party › numpy › append
Python Numpy append() - Add Elements to Array | Vultr Docs
April 10, 2025 - Here, python append to numpy array is done efficiently by appending elements to a list first, then converting it to a NumPy array in one step.
Python
docs.python.org › 3 › library › collections.html
collections — Container datatypes
Returns a new deque object initialized left-to-right (using append()) with data from iterable.
Stack Overflow
stackoverflow.com › questions › 72489660 › how-do-i-append-a-value-to-an-array-in-python
How do I append a value to an array in Python? - Stack Overflow
Second, concatenating with a structured array requires arguments with a matching dtype. On second thought, I am going to vote to close. Go back to your code and rewrite using lists and list appends.
Google Sites
sites.google.com › site › pythonpasapas › modules › array › array-append
Mon Python pas à pas - array.append ( )
element doit être une seule valeur ... type du tableau, Python lèvera une exception. La méthode array ( ).append ( ) ne peut ajouter qu'un seul et unique ......
Programiz
programiz.com › python-programming › numpy › methods › append
NumPy append()
import numpy as np array1 = np.array([0, 1, 2, 3]) array2 = np.array([4, 5, 6, 7]) # append values to an array array3 = np.append(array1, array2) print(array3)
Sarthaks eConnect
sarthaks.com › 3473395 › how-do-you-add-elements-to-an-array-in-python
How do you add elements to an array in Python? - Sarthaks eConnect | Largest Online Education Community
March 27, 2023 - LIVE Course for free · In Python, you can add elements to an array using various methods depending on the type of array you are working with
GeeksforGeeks
geeksforgeeks.org › python › numpy-append-python
numpy.append() in Python - GeeksforGeeks
April 14, 2025 - From the above output we can see that the numpy.append() function does not modify the original arrays (arr1 and arr2). Instead it creates a new array (arr3) with the combined elements. When working with multi-dimensional arrays you can specify the axis parameter to control how the values are appended.
Namehero
namehero.com › blog › how-to-append-an-item-to-a-python-array
How to Append an Item to a Python Array
April 17, 2024 - Here's how to append an item to a Python array, along with an explanation of the differences between an array and a list
Reddit
reddit.com › r/learnpython › append and write to an array?
r/learnpython on Reddit: Append and write to an array?
September 28, 2022 -
So if I have
x = [1, 2, 3] then x.append(4) will be [1, 2, 3, 4]
However, the code itself is unaffected by the code. So that's what I'm looking for right now. Possible how to write to an array in another file.
THANKS!
Top answer 1 of 4
5
x.append() will modify the list, I don't understand what you mean by "code itseld is unaffected"
2 of 4
2
Technically these are lists, not arrays (might lead to confusion), but I digress. So if I'm reading this correctly, you want to modify code in another file. You... probably shouldn't, as self-modifying code is rarely, if ever, a good idea. Instead, if you want persistent data, use something like a JSON file and store changes to that.
PhoenixNAP
phoenixnap.com › home › kb › devops and development › add elements to python array
Add Elements to Python Array (3 Methods)
December 15, 2025 - 3. Add one or more elements to an array end with the extend() method. Provide the elements in an iterable data type. The items in the iterable must match the array's data type. For example, add multiple elements to an array with a Python list:
DataCamp
campus.datacamp.com › courses › intro-to-python-for-data-science › chapter-3-functions-and-packages
List Methods (2) | Python
Use .append() twice to add the size of the poolhouse and the garage again: 24.5 and 15.45, respectively.