Python Program to Find Average of Array Elements

In this article, we will learn how to find the average of array elements using Python, along with examples to demonstrate the implementation. In this problem, we are given an array of integers, which may contain both positive and negative numbers. Our task is to calculate the average of all elements in the array.

Using the Brute Force Approach

This is a simple and direct approach that involves manually iterating through each element in the array to calculate the sum. Then, we divide the total sum by the count of elements to get the average. This approach is easier to understand but requires more code.

Steps for Implementation

• Define a function to take the array as an input parameter.
• Initialize a variable sum to 0 for tracking the total sum of elements.
• Use a loop to traverse the array and calculate the total sum.
• Handle cases where the array is empty by returning 0.
• Return the sum divided by the count of elements to get the average.

Example

def find_average(arr):
    if len(arr) == 0:
        return 0
    total_sum = 0
    for num in arr:
        total_sum += num
    return total_sum / len(arr)

arr = [1, 3, 5, 7, 9]
print("Average of array elements:", find_average(arr))

The output of the above code is ?

Average of array elements: 5.0

Using Python's Built-in sum() Function

In this approach, we use Python's built-in sum() function to simplify the calculation. The total sum of elements is obtained using sum(arr), and the length of the array is calculated using len(arr). This built-in function makes it easy to calculate the sum without using a loop.

Steps for Implementation

• Define a function and pass the array as a parameter.
• Use the sum() function to compute the total sum of elements.
• Handle the case where the array is empty by returning 0.
• Use the len() function to determine the count of elements.
• Return the average by dividing the total sum by the count.

Example

def find_average(arr):
    if len(arr) == 0:
        return 0
    total_sum = sum(arr)
    return total_sum / len(arr)

arr = [-2, 4, -6, 8, 10]
print("Average of array elements:", find_average(arr))

The output of the above code is ?

Average of array elements: 2.8

Using NumPy Library

NumPy is a popular library used for numerical computations. It provides a direct method, numpy.mean(), to calculate the average of given numbers. This method is better for large datasets and numerical applications. This approach is mainly used in data science and machine learning applications, providing additional functionalities like handling multi-dimensional arrays.

Steps for Implementation

• Import NumPy using import numpy as np.
• Use numpy.mean() to calculate the average of array elements.
• Handle cases where the array is empty.

Example

import numpy as np

def find_average(arr):
    if len(arr) == 0:
        return 0 
    return np.mean(arr)

arr = [-4, 9, 16, -2, 7]
print("Average of array elements:", find_average(arr))

The output of the above code is ?

Average of array elements: 5.2

Comparison of Methods

Conclusion

Use the sum() function for simple cases, NumPy's mean() for numerical computations, and manual loops when you need to understand the underlying process. The NumPy approach is most efficient for large datasets.