NumPy: Create a 2d array with 1 on the border and 0 inside
2D Array (Border 1, Inside 0)
Write a NumPy program to create a 2D array with 1 on the border and 0 inside.
Sample Solution:
Python Code:
# Importing the NumPy library with an alias 'np'
import numpy as np
# Creating a 5x5 NumPy array filled with ones
x = np.ones((5, 5))
# Printing the original array 'x'
print("Original array:")
print(x)
# Modifying the array 'x' to set the border elements to 1 and inner elements to 0
print("1 on the border and 0 inside in the array")
x[1:-1, 1:-1] = 0
# Printing the modified array 'x' showing 1s on the border and 0s inside
print(x)
Sample Output:
Original array: [[ 1. 1. 1. 1. 1.] [ 1. 1. 1. 1. 1.] [ 1. 1. 1. 1. 1.] [ 1. 1. 1. 1. 1.] [ 1. 1. 1. 1. 1.]] 1 on the border and 0 inside in the array [[ 1. 1. 1. 1. 1.] [ 1. 0. 0. 0. 1.] [ 1. 0. 0. 0. 1.] [ 1. 0. 0. 0. 1.] [ 1. 1. 1. 1. 1.]]
Explanation:
In the above code –
x = np.ones((5,5)): Creates a 5x5 NumPy array filled with ones.
x[1:-1,1:-1] = 0: This indexing operation sets the value of the inner elements of the array to zero by slicing the rows and columns from index 1 to the second last index (i.e., excluding the first and last rows and columns). The assignment operation (= 0) sets the selected elements to zero.
Python-Numpy Code Editor: