How to iterate over a list in Python?

List Iteration Methods in Python

Using the zip() Function:

• zip() combines multiple iterable objects element-wise.
• It returns an iterator of tuples containing elements from the input iterables at the same index.

list1 = [1, 2, 3]
list2 = ['a', 'b', 'c']
 
# Using zip() for iteration
for num, letter in zip(list1, list2):
    print(num, letter)
 

Using the itertools Module:

• The itertools module provides functions for creating and manipulating iterators efficiently.
• itertools.cycle() creates an infinite iterator cycling through elements of an iterable.

from itertools import cycle
 
colors = ['red', 'green', 'blue']
color_cycle = cycle(colors)
 
# Iterating infinitely through the cycle
for i in range(10):
    print(next(color_cycle))
 

Using the enumerate() Function:

• enumerate() is used to iterate over elements in a list while keeping track of their index or position.
• It returns tuples containing both the index and the element.

fruits = ['apple', 'banana', 'cherry']
 
# Using enumerate() for iteration with index
for index, fruit in enumerate(fruits):
    print(index, fruit)
 

Using the map() Function:

• map() applies a specified function to each item in an iterable and returns an iterable containing the results.
• It can be useful for performing operations on all elements of a list and collecting the results.

def square(x):
    return x * x
 
numbers = [1, 2, 3, 4]
 
# Using map() to apply the square function
squared_numbers = map(square, numbers)
 
# Converting the result to a list
squared_numbers = list(squared_numbers)
 
print(squared_numbers)