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NumPy: Test whether none of the elements of a given array is zero


Test None are Zero

Write a NumPy program to test whether none of the elements of a given array are zero.

This problem involves using NumPy to perform an element-wise check on an array. The task is to write a program that determines whether none of the elements in a given NumPy array are zero. This is useful for validating data where the presence of zero values might be problematic or indicate an error.

Sample Solution :

Python Code :

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

# Creating a NumPy array 'x' containing elements 1, 2, 3, and 4
x = np.array([1, 2, 3, 4])

# Printing the original array 'x'
print("Original array:")
print(x)

# Checking if none of the elements in the array 'x' is zero and printing the result
print("Test if none of the elements of the said array is zero:")
print(np.all(x))

# Reassigning array 'x' to a new array containing elements 0, 1, 2, and 3
x = np.array([0, 1, 2, 3])

# Printing the new array 'x'
print("Original array:")
print(x)

# Checking if none of the elements in the updated array 'x' is zero and printing the result
print("Test if none of the elements of the said array is zero:")
print(np.all(x))

Output:

Original array:
[1 2 3 4]
Test if none of the elements of the said array is zero:
True
Original array:
[0 1 2 3]
Test if none of the elements of the said array is zero:
False                         

Explanation:

In the above exercise -

x = np.array([1, 2, 3, 4]): This line creates a NumPy array 'x' with the elements 1, 2, 3, and 4.

print(np.all(x)): This line uses the np.all() function to test if all elements in the array 'x' are non-zero (i.e., not equal to zero). In this case, all elements are non-zero, so the function returns True.

x = np.array([0, 1, 2, 3]): This line creates a new NumPy array 'x' with the elements 0, 1, 2, and 3.

print(np.all(x)): This line uses the np.all() function again to test if all elements in the new array 'x' are non-zero. In this case, the first element is zero, so the function returns False.

Pictorial Presentation:

NumPy: Test whether none of the elements of a given array is zero.

Python-Numpy Code Editor: