Dada una array de n elementos, necesitamos encontrar la media geométrica de los números. Generalmente, la media geométrica de n números es la raíz enésima de su producto.
If there are n elements x1, x2, x3, . . ., xn in an array and if we want to calculate the geometric mean of the array elements is Geometric mean = (x1 * x2 * x3 * . . . * xn)1/n
Ejemplos:
Input : arr[] = {1, 2, 3, 4, 5, 6, 7, 8}
Output : 3.76435
= (1 * 2 * 3 * 4 * 5 * 6 * 7 * 8)1/8
= 403201/8
= 3.76435
Input : arr[] = {15, 12, 13, 19, 10}
Output : 13.447
= (15 * 12 * 13 * 19 * 10)1/5
= 4446001/5
= 13.477
Una solución simple es multiplicar primero todos los números y luego encontrar la (1/n)-ésima potencia de la multiplicación.
C++
// Program to calculate the geometric mean
// of the given array elements.
#include <bits/stdc++.h>
using namespace std;
// function to calculate geometric mean
// and return float value.
float geometricMean(int arr[], int n)
{
// declare product variable and
// initialize it to 1.
float product = 1;
// Compute the product of all the
// elements in the array.
for (int i = 0; i < n; i++)
product = product * arr[i];
// compute geometric mean through formula
// pow(product, 1/n) and return the value
// to main function.
float gm = pow(product, (float)1 / n);
return gm;
}
// Driver function
int main()
{
int arr[] = { 1, 2, 3, 4, 5, 6, 7, 8 };
int n = sizeof(arr) / sizeof(arr[0]);
cout << geometricMean(arr, n);
return 0;
}
Java
// Program to calculate the geometric mean
// of the given array elements.
import java.math.*;
class GFG{
// function to calculate geometric mean
// and return float value.
static float geometricMean(int arr[], int n)
{
// declare product variable and
// initialize it to 1.
float product = 1;
// Compute the product of all the
// elements in the array.
for (int i = 0; i < n; i++)
product = product * arr[i];
// compute geometric mean through
// formula pow(product, 1/n) and
// return the value to main function.
float gm = (float)Math.pow(product, (float)1 / n);
return gm;
}
// Driver function
public static void main(String args[])
{
int arr[] = { 1, 2, 3, 4, 5, 6, 7, 8 };
int n = arr.length ;
System.out.println(geometricMean(arr, n));
}
}
/*This code is contributed by Nikita Tiwari*/
Python
# Python Program to calculate the
# geometric mean of the given
# array elements.
import math
# function to calculate geometric
# mean and return float value.
def geometricMean(arr, n) :
# declare product variable and
# initialize it to 1.
product = 1
# Compute the product of all the
# elements in the array.
for i in range(0,n) :
product = product * arr[i]
# compute geometric mean through
# formula pow(product, 1/n) and
# return the value to main function.
gm = (float)(math.pow(product, (1 / n)))
return (float)(gm)
# Driver function
arr = [ 1, 2, 3, 4, 5, 6, 7, 8]
n = len(arr)
# to print 6 digits after decimal
print ('{0:.6f}'.format(geometricMean(arr, n)))
# This code is contributed by Nikita Tiwari
C#
// Program to calculate the geometric mean
// of the given array elements.
using System;
class GFG{
// function to calculate geometric mean
// and return float value.
static float geometricMean(int []arr, int n)
{
// declare product variable and
// initialize it to 1.
float product = 1;
// Compute the product of all the
// elements in the array.
for (int i = 0; i < n; i++)
product = product * arr[i];
// compute geometric mean through
// formula pow(product, 1/n) and
// return the value to main function.
float gm = (float)Math.Pow(product, (float)1 / n);
return gm;
}
// Driver function
public static void Main()
{
int []arr = { 1, 2, 3, 4, 5, 6, 7, 8 };
int n = arr.Length ;
Console.WriteLine(geometricMean(arr, n));
}
}
/*This code is contributed by vt_m*/
PHP
<?php
// Program to calculate the geometric mean
// of the given array elements.
// function to calculate geometric mean
// and return float value.
function geometricMean($arr, $n)
{
// declare product variable and
// initialize it to 1.
$product = 1;
// Compute the product of all the
// elements in the array.
for ($i = 0; $i < $n; $i++)
$product = $product * $arr[$i];
// compute geometric mean through formula
// pow(product, 1/n) and return the value
// to main function.
$gm = pow($product, (float)(1 / $n));
return $gm;
}
// Driver Code
$arr = array(1, 2, 3, 4, 5, 6, 7, 8);
$n = sizeof($arr);
echo(geometricMean($arr, $n));
// This code is contributed by Ajit.
?>
Javascript
<script>
// Javascript program to calculate the geometric mean
// of the given array elements.
// function to calculate geometric mean
// and return float value.
function geometricMean(arr, n)
{
// declare product variable and
// initialize it to 1.
let product = 1;
// Compute the product of all the
// elements in the array.
for (let i = 0; i < n; i++)
product = product * arr[i];
// compute geometric mean through
// formula pow(product, 1/n) and
// return the value to main function.
let gm = Math.pow(product, 1 / n);
return gm;
}
// driver function
let arr = [ 1, 2, 3, 4, 5, 6, 7, 8 ];
let n = arr.length ;
document.write(geometricMean(arr, n));
// This code is contributed by code_hunt.
</script>
Producción:
3.76435
La solución anterior simplemente provoca un desbordamiento. Una mejor solución es usar log. Hay n números y necesitamos calcular la media geométrica usando la fórmula:
Geometric mean = Antilog((log(x1) + log(x2) +
log(x3) + . . . + log(xn))/n)
Para calcular el Antilog en programación usamos la función exponente (exp()) .
C++
// Program to calculate the geometric mean
// of the given array elements.
#include <bits/stdc++.h>
using namespace std;
// function to calculate geometric mean
// and return float value.
float geometricMean(int arr[], int n)
{
// declare sum variable and
// initialize it to 1.
float sum = 0;
// Compute the sum of all the
// elements in the array.
for (int i = 0; i < n; i++)
sum = sum + log(arr[i]);
// compute geometric mean through formula
// antilog(((log(1) + log(2) + . . . + log(n))/n)
// and return the value to main function.
sum = sum / n;
return exp(sum);
}
// Driver function
int main()
{
int arr[] = { 1, 2, 3, 4, 5, 6, 7, 8 };
int n = sizeof(arr) / sizeof(arr[0]);
// function call
cout << geometricMean(arr, n);
return 0;
}
Java
// Java Program to calculate the geometric mean
// of the given array elements.
import java.io.*;
class GFG
{
// function to calculate geometric mean
// and return float value.
static float geometricMean(int []arr, int n)
{
// declare sum variable and
// initialize it to 1.
float sum = 0;
// Compute the sum of all the
// elements in the array.
for (int i = 0; i < n; i++)
sum = sum + (float)Math.log(arr[i]);
// compute geometric mean through formula
// antilog(((log(1) + log(2) + . . . + log(n))/n)
// and return the value to main function.
sum = sum / n;
return (float)Math.exp(sum);
}
// Driver function
public static void main (String[] args)
{
int []arr = { 1, 2, 3, 4, 5, 6, 7, 8 };
int n = arr.length;
// function call
System.out.println(geometricMean(arr, n));
}
}
// This code is contributed by vt_m.
Python3
# Program to calculate the # geometric mean of the # given array elements. import math # function to calculate # geometric mean and # return float value. def geometricMean(arr, n): # declare sum variable and # initialize it to 1. sum = 0; # Compute the sum of all # the elements in the array. for i in range(n): sum = sum + math.log(arr[i]); # compute geometric mean # through formula antilog # (((log(1) + log(2) + . . # ... + log(n))/n) # and return the value to # main function. sum = sum / n; return math.exp(sum); # Driver Code arr= [ 1, 2, 3, 4, 5, 6, 7, 8 ]; n = len(arr); # function call print(geometricMean(arr, n)); # This code is contributed by mits.
C#
// Program to calculate the geometric mean
// of the given array elements.
using System;
class GFG {
// function to calculate geometric mean
// and return float value.
static float geometricMean(int []arr, int n)
{
// declare sum variable and
// initialize it to 1.
float sum = 0;
// Compute the sum of all the
// elements in the array.
for (int i = 0; i < n; i++)
sum = sum + (float)Math.Log(arr[i]);
// compute geometric mean through formula
// antilog(((log(1) + log(2) + . . . + log(n))/n)
// and return the value to main function.
sum = sum / n;
return (float)Math.Exp(sum);
}
// Driver function
public static void Main ()
{
int []arr = { 1, 2, 3, 4, 5, 6, 7, 8 };
int n = arr.Length;
// function call
Console.WriteLine(geometricMean(arr, n));
}
}
// This code is contributed by vt_m.
PHP
<?php
// Program to calculate the geometric mean
// of the given array elements.
// function to calculate geometric mean
// and return float value.
function geometricMean($arr, $n)
{
// declare sum variable and
// initialize it to 1.
$sum = 0;
// Compute the sum of all the
// elements in the array.
for($i = 0; $i < $n; $i++)
$sum = $sum + log($arr[$i]);
// compute geometric mean
// through formula
// antilog(((log(1) + log(2) +
// . . . + log(n))/n)
// and return the value
$sum = $sum / $n;
return exp($sum);
}
// Driver Code
$arr = array(1, 2, 3, 4, 5, 6, 7, 8);
$n = count($arr);
// function call
echo geometricMean($arr, $n);
// This code is contributed by anuj_67.
?>
Javascript
<script>
// Program to calculate the geometric mean
// of the given array elements.
// function to calculate geometric mean
// and return float value.
function geometricMean(arr, n)
{
// declare sum variable and
// initialize it to 1.
var sum = 0;
// Compute the sum of all the
// elements in the array.
for (var i = 0; i < n; i++)
sum = sum + Math.log(arr[i]);
// compute geometric mean through formula
// antilog(((log(1) + log(2) + . . . + log(n))/n)
// and return the value to main function.
sum = sum / n;
return Math.exp(sum);
}
// Driver function
var arr = [ 1, 2, 3, 4, 5, 6, 7, 8 ];
var n = arr.length;
// function call
document.write(geometricMean(arr, n).toFixed(5));
// This code is contributed by bunnyram19.
</script>
Producción:
3.76435
Este artículo es una contribución de Dharmendra Kumar . Si te gusta GeeksforGeeks y te gustaría contribuir, también puedes escribir un artículo usando write.geeksforgeeks.org o enviar tu artículo por correo a contribuido@geeksforgeeks.org. Vea su artículo que aparece en la página principal de GeeksforGeeks y ayude a otros Geeks.
Escriba comentarios si encuentra algo incorrecto o si desea compartir más información sobre el tema tratado anteriormente.
Publicación traducida automáticamente
Artículo escrito por GeeksforGeeks-1 y traducido por Barcelona Geeks. The original can be accessed here. Licence: CCBY-SA