How to add a vector to a given Numpy array?

In this problem, we have to add a vector/array to a numpy array. We will define the numpy array as well as the vector and add them to get the result array using NumPy's broadcasting capabilities.

Algorithm

Step 1: Define a numpy array.
Step 2: Define a vector.
Step 3: Add vector to each row of the original array using broadcasting.
Step 4: Print the result array.

Method 1: Using Broadcasting (Recommended)

NumPy automatically broadcasts the vector to each row ?

import numpy as np

original_array = np.array([[1, 2, 3], [4, 5, 6], [7, 8, 9], [10, 11, 12]])
print("Original Array:")
print(original_array)

vector = np.array([1, 1, 0])
print("\nVector:", vector)

# Simple broadcasting addition
result = original_array + vector
print("\nResult:")
print(result)

Original Array:
[[ 1  2  3]
 [ 4  5  6]
 [ 7  8  9]
 [10 11 12]]

Vector: [1 1 0]

Result:
[[ 2  3  3]
 [ 5  6  6]
 [ 8  9  9]
 [11 12 12]]

Method 2: Using Loop (Manual Approach)

Manually iterate through each row and add the vector ?

import numpy as np

original_array = np.array([[1, 2, 3], [4, 5, 6], [7, 8, 9], [10, 11, 12]])
vector = np.array([1, 1, 0])

result = np.empty_like(original_array)
for i in range(len(original_array)):
    result[i, :] = original_array[i, :] + vector

print("Result using loop:")
print(result)

Result using loop:
[[ 2  3  3]
 [ 5  6  6]
 [ 8  9  9]
 [11 12 12]]

How Broadcasting Works

NumPy automatically handles the dimension alignment. The vector [1, 1, 0] is broadcast to match each row of the 4×3 array.

Comparison

Conclusion

Use NumPy broadcasting (array + vector) for efficient vector addition to arrays. Broadcasting automatically handles dimension alignment and provides better performance than manual loops.