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Moving average of array elements

The moving average is a concept used in statistics and signal processing to analyze a sequence of data points by calculating the average of a certain number of adjacent values. It is often used to smooth out fluctuations and reveal underlying trends in data.

Problem Statement

Given an array of integer elements and a specified window size, the problem is to calculate the moving average of the array elements by considering each window of consecutive elements.

Idea to Solve the Problem

The idea to calculate the moving average is straightforward. For each window of consecutive elements, you sum up the elements within that window and then divide by the number of elements in the window to find the average. As you move the window along the array, the calculated average will give you insight into the trend of the data.

Pseudocode


method findAverage(arr, n)
    sum = 0.0
    for i from 0 to n - 1
        sum = sum + arr[i]
        if i ≠ 0
            print ","
        print " " + (sum / (i + 1))

Algorithm Explanation

  1. The findAverage method takes an array arr and the size n of the array as inputs.

  2. Initialize a variable sum to keep track of the sum of elements within the current window.

  3. Loop through the array from index 0 to n - 1.

  4. For each element, add it to the sum.

  5. If the index i is not 0, print a comma to separate the average values.

  6. Print the calculated moving average, which is the sum divided by the current window size (i + 1).

Code Solution

// Java program for
// Moving average of array elements 
public class Average
{
	public void findAverage(int[] arr, int n)
	{
		double sum = 0.0;
		for (int i = 0; i < n; ++i)
		{
			// Calculate sum
			sum += arr[i];
			if (i != 0)
			{
				System.out.print(",");
			}
			// Display average
			System.out.print(" " + (sum / (i + 1)));
		}
	}
	public static void main(String[] args)
	{
		Average task = new Average();
		// Array of integer elements
		int[] arr = {
			4 , 6 , 9 , 20 , 12 , 34 , 25
		};
		// Get the size
		int n = arr.length;
		// Test
		task.findAverage(arr, n);
	}
}

Output

 4.0, 5.0, 6.333333333333333, 9.75, 10.2, 14.166666666666666, 15.714285714285714
// C Program
// Moving average of array elements 
#include <stdio.h>

void findAverage(int arr[], int n)
{
	double sum = 0.0;
	for (int i = 0; i < n; ++i)
	{
		// Calculate sum
		sum += arr[i];
		// Display average
		printf(" %lf", (sum / (i + 1)));
	}
}
int main()
{
	// Array of integer elements
	int arr[] = {
		4 , 6 , 9 , 20 , 12 , 34 , 25
	};
	// Get the size
	int n = sizeof(arr) / sizeof(arr[0]);
	// Test
	findAverage(arr, n);
	return 0;
}

Output

 4.000000 5.000000 6.333333 9.750000 10.200000 14.166667 15.714286
// Include header file
#include <iostream>

using namespace std;
// C++ program for
// Moving average of array elements
class Average
{
	public: void findAverage(int arr[], int n)
	{
		double sum = 0.0;
		for (int i = 0; i < n; ++i)
		{
			// Calculate sum
			sum += arr[i];
			if (i != 0)
			{
				cout << ",";
			}
			// Display average
			cout << " " << (sum / (i + 1));
		}
	}
};
int main()
{
	Average *task = new Average();
	// Array of integer elements
	int arr[] = {
		4 , 6 , 9 , 20 , 12 , 34 , 25
	};
	// Get the size
	int n = sizeof(arr) / sizeof(arr[0]);
	// Test
	task->findAverage(arr, n);
	return 0;
}

Output

 4, 5, 6.33333, 9.75, 10.2, 14.1667, 15.7143
// Include namespace system
using System;
// Csharp program for
// Moving average of array elements
public class Average
{
	public void findAverage(int[] arr, int n)
	{
		double sum = 0.0;
		for (int i = 0; i < n; ++i)
		{
			// Calculate sum
			sum += arr[i];
			if (i != 0)
			{
				Console.Write(",");
			}
			// Display average
			Console.Write(" " + (sum / (i + 1)));
		}
	}
	public static void Main(String[] args)
	{
		Average task = new Average();
		// Array of integer elements
		int[] arr = {
			4 , 6 , 9 , 20 , 12 , 34 , 25
		};
		// Get the size
		int n = arr.Length;
		// Test
		task.findAverage(arr, n);
	}
}

Output

 4, 5, 6.33333333333333, 9.75, 10.2, 14.1666666666667, 15.7142857142857
package main
import "fmt"
// Go program for
// Moving average of array elements
type Average struct {}
func getAverage() * Average {
	var me *Average = &Average {}
	return me
}
func(this Average) findAverage(arr[] int, n int) {
	var sum float64 = 0.0
	for i := 0 ; i < n ; i++ {
		// Calculate sum
		sum += float64(arr[i])
		if i != 0 {
			fmt.Print(",")
		}
		// Display average
		fmt.Print(" ", (sum / float64(i + 1)))
	}
}
func main() {
	var task * Average = getAverage()
	// Array of integer elements
	var arr = [] int { 4 , 6 , 9 , 20 , 12 , 34 , 25 }
	// Get the size
	var n int = len(arr)
	// Test
	task.findAverage(arr, n)
}

Output

 4.0, 5.0, 6.333333333333333, 9.75, 10.2, 14.166666666666666, 15.714285714285714
<?php
// Php program for
// Moving average of array elements
class Average
{
	public	function findAverage($arr, $n)
	{
		$sum = 0.0;
		for ($i = 0; $i < $n; ++$i)
		{
			// Calculate sum
			$sum += $arr[$i];
			if ($i != 0)
			{
				echo(",");
			}
			// Display average
			echo(" ".($sum / ($i + 1)));
		}
	}
}

function main()
{
	$task = new Average();
	// Array of integer elements
	$arr = array(4, 6, 9, 20, 12, 34, 25);
	// Get the size
	$n = count($arr);
	// Test
	$task->findAverage($arr, $n);
}
main();

Output

 4, 5, 6.3333333333333, 9.75, 10.2, 14.166666666667, 15.714285714286
// Node JS program for
// Moving average of array elements
class Average
{
	findAverage(arr, n)
	{
		var sum = 0.0;
		for (var i = 0; i < n; ++i)
		{
			// Calculate sum
			sum += arr[i];
			if (i != 0)
			{
				process.stdout.write(",");
			}
			// Display average
			process.stdout.write(" " + (sum / (i + 1)));
		}
	}
}

function main()
{
	var task = new Average();
	// Array of integer elements
	var arr = [4, 6, 9, 20, 12, 34, 25];
	// Get the size
	var n = arr.length;
	// Test
	task.findAverage(arr, n);
}
main();

Output

 4, 5, 6.333333333333333, 9.75, 10.2, 14.166666666666666, 15.714285714285714
#  Python 3 program for
#  Moving average of array elements
class Average :
	def findAverage(self, arr, n) :
		sum = 0.0
		i = 0
		while (i < n) :
			#  Calculate sum
			sum += arr[i]
			if (i != 0) :
				print(",", end = "")
			
			#  Display average
			print(" ", (sum / (i + 1)), end = "")
			i += 1
		
	

def main() :
	task = Average()
	#  Array of integer elements
	arr = [4, 6, 9, 20, 12, 34, 25]
	#  Get the size
	n = len(arr)
	#  Test
	task.findAverage(arr, n)

if __name__ == "__main__": main()

Output

  4.0,  5.0,  6.333333333333333,  9.75,  10.2,  14.166666666666666,  15.714285714285714
#  Ruby program for
#  Moving average of array elements
class Average 
	def findAverage(arr, n) 
		sum = 0.0
		i = 0
		while (i < n) 
			#  Calculate sum
			sum += arr[i]
			if (i != 0) 
				print(",")
			end

			#  Display average
			print(" ", (sum / (i + 1)))
			i += 1
		end

	end

end

def main() 
	task = Average.new()
	#  Array of integer elements
	arr = [4, 6, 9, 20, 12, 34, 25]
	#  Get the size
	n = arr.length
	#  Test
	task.findAverage(arr, n)
end

main()

Output

 4.0, 5.0, 6.333333333333333, 9.75, 10.2, 14.166666666666666, 15.714285714285714
// Scala program for
// Moving average of array elements
class Average()
{
	def findAverage(arr: Array[Int], n: Int): Unit = {
		var sum: Double = 0.0;
		var i: Int = 0;
		while (i < n)
		{
			// Calculate sum
			sum += arr(i);
			if (i != 0)
			{
				print(",");
			}
			// Display average
			print(" " + (sum / (i + 1)));
			i += 1;
		}
	}
}
object Main
{
	def main(args: Array[String]): Unit = {
		var task: Average = new Average();
		// Array of integer elements
		var arr: Array[Int] = Array(4, 6, 9, 20, 12, 34, 25);
		// Get the size
		var n: Int = arr.length;
		// Test
		task.findAverage(arr, n);
	}
}

Output

 4.0, 5.0, 6.333333333333333, 9.75, 10.2, 14.166666666666666, 15.714285714285714
import Foundation;
// Swift 4 program for
// Moving average of array elements
class Average
{
	func findAverage(_ arr: [Int], _ n: Int)
	{
		var sum: Double = 0.0;
		var i: Int = 0;
		while (i < n)
		{
			// Calculate sum
			sum += Double(arr[i]);
			if (i  != 0)
			{
				print(",", terminator: "");
			}
			// Display average
			print(" ", (sum / Double(i + 1)), terminator: "");
			i += 1;
		}
	}
}
func main()
{
	let task: Average = Average();
	// Array of integer elements
	let arr: [Int] = [4, 6, 9, 20, 12, 34, 25];
	// Get the size
	let n: Int = arr.count;
	// Test
	task.findAverage(arr, n);
}
main();

Output

  4.0,  5.0,  6.33333333333333,  9.75,  10.2,  14.1666666666667,  15.7142857142857
// Kotlin program for
// Moving average of array elements
class Average
{
	fun findAverage(arr: Array < Int > , n: Int): Unit
	{
		var sum: Double = 0.0;
		var i: Int = 0;
		while (i < n)
		{
			// Calculate sum
			sum += arr[i];
			if (i != 0)
			{
				print(",");
			}
			// Display average
			print(" " + (sum / (i + 1)));
			i += 1;
		}
	}
}
fun main(args: Array < String > ): Unit
{
	val task: Average = Average();
	// Array of integer elements
	val arr: Array < Int > = arrayOf(4, 6, 9, 20, 12, 34, 25);
	// Get the size
	val n: Int = arr.count();
	// Test
	task.findAverage(arr, n);
}

Output

 4.0, 5.0, 6.333333333333333, 9.75, 10.2, 14.166666666666666, 15.714285714285714

Time Complexity

The time complexity of this algorithm is O(n), where n is the number of elements in the array. This is because the algorithm iterates through the array once, performing constant-time operations for each element.

Last updated on by Kalkicode




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