Numpy program to Transpose and add arrays

Last update on March 26 2025 13:15:54 (UTC/GMT +8 hours)

7. Transpose and Add 1D Array to Each Row

Given a 2D array of shape (3, 5) and a 1D array of shape (3,). Write a Numpy program that transposes the 2D array and add the 1D array to each row of the transposed array.

Sample Solution:

Python Code:

import numpy as np

# Initialize the 2D array of shape (3, 5)
array_2d = np.array([[1, 2, 3, 4, 5],
                     [6, 7, 8, 9, 10],
                     [11, 12, 13, 14, 15]])

# Initialize the 1D array of shape (3,)
array_1d = np.array([1, 2, 3])

# Transpose the 2D array to get shape (5, 3)
transposed_array = np.transpose(array_2d)

# Add the 1D array to each row of the transposed array
# Broadcasting is used here to add 1D array to each row of transposed 2D array
result_array = transposed_array + array_1d

# Display the result
print(result_array)

Output:

[[ 2  8 14]
 [ 3  9 15]
 [ 4 10 16]
 [ 5 11 17]
 [ 6 12 18]]

Explanation:

• Importing numpy: We first import the numpy library for array manipulations.
• Initializing arrays: Two arrays are initialized, one 2D array of shape (3, 5) and one 1D array of shape (3,).
• Transposing the 2D array: The 2D array is transposed to get a new shape of (5, 3).
• Broadcasting and Addition: The 1D array is added to each row of the transposed array using broadcasting.
• Displaying result: The resulting array is printed out.

For more Practice: Solve these Related Problems:

• Transpose a given 2D array and then add a 1D array to each row using broadcasting, verifying the new shape.
• Create a function that adds a constant vector to the transposed array and then transposes it back to the original layout.
• Implement a solution that compares the result of transposing and adding with the result of adding and then transposing.
• Test the operation on arrays with different dimensions to ensure broadcasting applies correctly to rows.

Python-Numpy Code Editor:

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