Python list comprehension

Python list is used to store multiple value with different data types, values inside a list can be accessed or retrieved using index.

Create a new list with the addition of each number in an existing list

consider the following example if we want to do some operation the values inside the list we have to python for loop to iterate over each one.

l = [1,2,3,4,5]
m = []
for i in l:
    m.append(i+i)
print("m:", m) # Output: m: [2, 4, 6, 8, 10]

Python have its own pythonic style of writing the code in a single line.

l = [1,2,3,4,5]
m = [i+i for i in l]
print("m:", m) # Output: m: [2, 4, 6, 8, 10]

Creating a new list out of the first letter of every word in a string

myString = "Hello World Python Code"

myList = []
for s in myString.split(" "):
    myList.append(s[0])

print("myList:", myList) # Output: myList: ['H', 'W', 'P', 'C']

Using list comprehension

myString = "Hello World Python Code"

myList = [s[0] for s in myString.split(" ")]

print("myList:", myList) # Output: m: [2, 4, 6, 8, 10]

Explore Other Related Articles

How to combine two dictionaries in python using different methods
How to check if a key exists in a dictionary python
Python try exception tutorial
Python classes and objects tutorial
Python Recursion Function Tutorial
Python Lambda Function Tutorial