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This tutorial will demonstrate various ways to perform multiplication of two list elements in Python. Suppose we have two lists of integers of the same dimension, and we want to multiply the elements in the first list with the elements at the same position in the second list to get a resulting list of the same dimension.

zip()Multiply two lists using the

The built-in tuple method in Python zip()accepts one or more iterables and aggregates the iterables into a tuple. Lists like _and_ [1,2,3]will [4,5,6]become [(1, 4), (2, 5), (3, 6)]_. Using map()the _ method, we access both lists element-wise and use list comprehension to get the required list.

The following code example shows how to use zip()with list comprehensions to reuse 1D and 2D lists.

list1 = [2, 4, 5, 3, 5, 4]
list2 = [4, 1, 2, 9, 7, 5]
product = [x * y for x, y in zip(list1, list2)]
print(product)

Output:

[8, 4, 10, 27, 35, 20]

Multiplication of 2D lists:

list1 = [[2, 4, 5], [3, 5, 4]]
list2 = [[4, 1, 2], [9, 7, 5]]
product = [[0] * 3] * 2

for x in range(len(list1)):
    product[x] = [a * b for a, b in zip(list1[x], list2[x])]

print(product)

Output:

[[8, 4, 10], [27, 35, 20]]

numpy.multiply()Multiply two lists using the

NumPyThe method of the Python library multiply()takes two arrays/lists as input and returns an array/list after element-wise multiplication. This method is straightforward because we don't need to do any extra work for the two-dimensional multiplication, but the disadvantage of this method is that it NumPycannot be used without the library.

The following code example demonstrates how to use numpy.multiply()the multiplication method to multiply 1D and 2D lists in Python.

• 1D multiplication:

import numpy as np

list1 = [12, 3, 1, 2, 3, 1]
list2 = [13, 2, 3, 5, 3, 4]

product = np.multiply(list1, list2)
print(product)

Output:

[156   6   3  10   9   4]

• 2D multiplication:

import numpy as np

list1 = [[12, 3, 1], [2, 3, 1]]
list2 = [[13, 2, 3], [5, 3, 4]]

product = np.multiply(list1, list2)
print(product)

Output:

[[156   6   3]
 [ 10   9   4]]

map()Multiply two lists in Python using the

mapFunctions take a function and one or more iterables as input, and return an iterable that applies the provided function to the input list.

We can use the multiplication function in Python to perform 1D and 2D element-wise multiplication of map()two lists by passing map()the two lists as arguments to the multiplication function. The following code example demonstrates how we can use map()multiplication to perform multiplication of two Python lists.

Example code for 1D multiplication:

list1 = [2, 4, 5, 3, 5, 4]
list2 = [4, 1, 2, 9, 7, 5]
product = list(map(lambda x, y: x * y, list1, list2))
print(product)

Output:

[8, 4, 10, 27, 35, 20]

Example code for 2D multiplication:

list1 = [[2, 4, 5], [3, 5, 4]]
list2 = [[4, 1, 2], [9, 7, 5]]
product = [[0] * 3] * 2

for x in range(len(list1)):
    product[x] = list(map(lambda a, b: a * b, list1[x], list2[x]))

print(product)

Output:

[[8, 4, 10], [27, 35, 20]]