NumPy: Count the number of "P" in a given array, element-wise

Last update on March 25 2025 12:19:34 (UTC/GMT +8 hours)

15. Count Occurrences of "P" in Strings

Write a NumPy program to count the number of "P" in a given array, element-wise.

Sample Solution:

Python Code:

# Importing necessary library
import numpy as np

# Creating a NumPy array containing strings
x1 = np.array(['Python', 'PHP', 'JS', 'examples', 'html'], dtype=np.str)

# Displaying the content of the original array
print("\nOriginal Array:")
print(x1)

# Counting the occurrences of the character 'P' in each string of the array x1
print("Number of ‘P’:")
r = np.char.count(x1, "P")
print(r) 

Sample Input:

(['Python', 'PHP', 'JS', 'examples', 'html'], dtype=np.str)

Sample Output:

Original Array:
['Python' 'PHP' 'JS' 'examples' 'html']
Number of ‘P’:
[1 2 0 0 0]

Explanation:

In the above exercise –

x1 = np.array(['Python', 'PHP', 'JS', 'examples', 'html'], dtype=np.str): Creates a NumPy array named x1 which contains five strings as its elements.

r = np.char.count(x1, "P"): The np.char.count() method is used to count the number of occurrences of the character "P" in each of the strings of the array x1. The resulting count values are stored in a newly created NumPy array named r.

Pictorial Presentation:

For more Practice: Solve these Related Problems:

• Create a function that counts the occurrences of the letter "P" in each string of an array using np.char.count.
• Implement a solution that handles both uppercase and lowercase "p" by summing counts from both np.char.count('P') and np.char.count('p').
• Test the function on an array of words and verify that the counts match manual inspection.
• Chain the count operation with a filter that returns only strings containing more than one occurrence of "P."

Python-Numpy Code Editor:

Previous: Write a NumPy program to test equal, not equal, greater equal, greater and less test of all the elements of two given arrays.
Next: Write a NumPy program to count the lowest index of "P" in a given array, element-wise.