NumPy: Extract first and second elements of the first and second rows from a given (4x4) array
Extract First & Second Elements of First Two Rows
Write a NumPy program to extract the first and second elements of the first and second rows from a given (4x4) array.
Pictorial Presentation:
Sample Solution:
Python Code:
# Importing the NumPy library and aliasing it as 'np'
import numpy as np
# Creating a NumPy array 'arra_data' containing integers from 0 to 15 and reshaping it into a 4x4 matrix
arra_data = np.arange(0, 16).reshape((4, 4))
# Displaying a message indicating the original array will be printed
print("Original array:")
# Printing the original 4x4 array 'arra_data'
print(arra_data)
# Displaying a message indicating the extracted data (first and second elements of the first and second rows)
print("\nExtracted data: First and second elements of the first and second rows")
# Using slicing to extract the first two rows and first two columns (0:2 refers to 0th and 1st indices)
print(arra_data[0:2, 0:2])
Sample Output:
Original array: [[ 0 1 2 3] [ 4 5 6 7] [ 8 9 10 11] [12 13 14 15]] Extracted data: First and second elements of the first and second rows [[0 1] [4 5]]
Explanation:
arra_data = np.arange(0, 16).reshape((4, 4)): It creates a 1-dimensional NumPy array with elements from 0 to 15 (excluding 16) using np.arange(0, 16) and then reshapes it into a 2-dimensional array with 4 rows and 4 columns using .reshape((4, 4)).print(arra_data): This line prints the ‘arra_data’ array.
print(arra_data[0:2, 0:2]): It prints a subarray of ‘arra_data’ containing the first two rows and the first two columns. The slicing syntax 0:2 indicate elements from index 0 (inclusive) to index 2 (exclusive).
Python-Numpy Code Editor:
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