NumPy: Create a 10x10 matrix, in which the elements on the borders will be equal to 1, and inside 0

NumPy: Basic Exercise-28 with Solution

Write a NumPy program to create a 10x10 matrix, in which the elements on the borders will be equal to 1, and inside 0.

Sample Solution :

Python Code :

# Importing the NumPy library with an alias 'np'
import numpy as np

# Creating a 10x10 matrix filled with ones using np.ones()
x = np.ones((10, 10))

# Setting the inner values of the matrix 'x' (excluding the borders) to 0 using slicing
x[1:-1, 1:-1] = 0

# Printing the modified matrix 'x'
print(x) 

Sample Output:

[[ 1.  1.  1.  1.  1.  1.  1.  1.  1.  1.]
 [ 1.  0.  0.  0.  0.  0.  0.  0.  0.  1.]
 [ 1.  0.  0.  0.  0.  0.  0.  0.  0.  1.]
 [ 1.  0.  0.  0.  0.  0.  0.  0.  0.  1.]
 [ 1.  0.  0.  0.  0.  0.  0.  0.  0.  1.]
 [ 1.  0.  0.  0.  0.  0.  0.  0.  0.  1.]
 [ 1.  0.  0.  0.  0.  0.  0.  0.  0.  1.]
 [ 1.  0.  0.  0.  0.  0.  0.  0.  0.  1.]
 [ 1.  0.  0.  0.  0.  0.  0.  0.  0.  1.]
 [ 1.  1.  1.  1.  1.  1.  1.  1.  1.  1.]]                         

Explanation:

In the above code -

np.ones((10, 10)) creates a 10x10 array 'x' filled with ones.

‘x[1:-1, 1:-1] = 0’ uses array slicing to select the inner region of the array 'x' and set its elements to zeros. The slice 1:-1 means "from the second element to the second-to-last element" in both the rows and columns. As a result, the inner region of the array will be filled with zeros, leaving a border of ones.

Finally print(x) prints the modified array to the console.

Pictorial Presentation:

Python-Numpy Code Editor:

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