How to find the average of elements of an integer array in C#?

Finding the average of elements in an integer array is a common programming task in C#. The average is calculated by dividing the sum of all elements by the total number of elements in the array.

Syntax

The basic approach involves three steps −

int[] array = {element1, element2, element3, ...};
int sum = 0;
for (int i = 0; i < array.Length; i++) {
    sum += array[i];
}
int average = sum / array.Length;

Using For Loop to Calculate Average

The traditional approach uses a for loop to iterate through the array and accumulate the sum −

using System;

public class Program {
    public static void Main() {
        int[] myArr = new int[6] {
            8,
            4,
            2,
            5,
            9,
            14
        };
        
        int len = myArr.Length;
        int sum = 0;
        int average = 0;
        
        for (int i = 0; i < len; i++) {
            sum += myArr[i];
        }
        
        average = sum / len;
        
        Console.WriteLine("Array elements: [" + string.Join(", ", myArr) + "]");
        Console.WriteLine("Sum = " + sum);
        Console.WriteLine("Average of integer elements = " + average);
    }
}

The output of the above code is −

Array elements: [8, 4, 2, 5, 9, 14]
Sum = 42
Average of integer elements = 7

Using LINQ Average Method

C# provides a built-in Average() method through LINQ that simplifies the calculation −

using System;
using System.Linq;

public class Program {
    public static void Main() {
        int[] myArr = {15, 10, 5, 20, 25, 30};
        
        double average = myArr.Average();
        
        Console.WriteLine("Array elements: [" + string.Join(", ", myArr) + "]");
        Console.WriteLine("Average using LINQ: " + average);
    }
}

The output of the above code is −

Array elements: [15, 10, 5, 20, 25, 30]
Average using LINQ: 17.5

Handling Decimal Precision

When calculating averages, consider using double to preserve decimal precision −

using System;

public class Program {
    public static void Main() {
        int[] numbers = {7, 8, 9};
        
        // Integer division (truncates decimal)
        int intAverage = numbers.Sum() / numbers.Length;
        
        // Double division (preserves decimal)
        double doubleAverage = (double)numbers.Sum() / numbers.Length;
        
        Console.WriteLine("Array elements: [" + string.Join(", ", numbers) + "]");
        Console.WriteLine("Integer average: " + intAverage);
        Console.WriteLine("Double average: " + doubleAverage);
    }
}

The output of the above code is −

Array elements: [7, 8, 9]
Integer average: 8
Double average: 8

Comparison of Methods

Conclusion

Finding the average of an integer array in C# can be accomplished using a traditional for loop or the built-in LINQ Average() method. Consider using double data types when decimal precision is important for your calculations.