Mean: it is the average of all elements in a set of values. Mean add the values in a set and divide the sum with the number of elements. For example, if a set has 3 numbers [1,2,3] then the mean is calculated using 1+2+3 = 6/3 =2.
Variance: it is the average of the squared difference between the mean and the values of the data set. It is called the spread of data within a sample of data.
Standard deviation: after we found the variance, we can calculate the standard deviation by taking the square root of the variance.
In this C program, we take the values and save that in an array. The mean calculation is done by taking the average of the sum by using a for loop. After that, we need to calculate variance using the formula.
v_sum = v_sum + pow((nums[i] - avrg),2);
var = v_sum / (float) n;
After calculating the variance, it is easy to find the standard deviation. for that, we use the sd = sqrt(var) formula. Finally, we have to display the results using printf.
STEP 1: Include the Header files into the C program to use the built-in functions.
STEP 2: Define and initialize the Array and the variables.
STEP 3: Accept the value for the number of terms from the user using printf and scanf functions.
STEP 4: Accept the numbers from the user and add those numbers into an Array using for loop and scanf.
STEP 5: Open a for loop from i=0 to the number of terms n to calculate the mean. Add each element and save it in sum, and divide sum with the number of terms.
STEP 6: Open another for loop from i=0 to n to find the variance. In each iteration of loop calculate,
v_sum = v_sum + pow((nums[i] - mean),2) , and after that use the formula var = v_sum / (float) n
STEP 8: Calculate the Standard deviation sd by taking the square root of var.
STEP 10: print the mean, sd, and var using printf.
#include <stdio.h>
#include <math.h>
#define MAXSIZE 10
void main()
{
float nums[MAXSIZE];
int i, n;
float mean, var, sd, sum=0, v_sum=0; /* declares the variables*/
printf("Enter the number of elements\n"); /* accepts values from user */
scanf("%d", &n);
printf("Enter %d real numbers\n",n);
for (i = 0; i < n; i++)
{
scanf("%f", & nums[i]);
}
for(i=0; i<n; i++) /* Compute the sum of all elements */
{
sum = sum + nums[i];
}
mean = sum /(float) n; /* Calculating the mean using the equation */
for(i=0; i<n; i++) /* Compute variance and standard deviation */
{
v_sum= v_sum + pow((nums[i] - mean), 2);
}
var = v_sum / (float) n; /* calculate the variance using general equation */
sd = sqrt(var); /* calculating standard deviation */
/* prints the output mean, standard deviation, and variance */
printf("Mean of all elements = %.2f\n", mean);
printf("The variance of all elements = %.2f\n", var);
printf("Standard deviation SD = %.2f\n", sd);
}
Enter the number of elements 6 Enter 6 real numbers 12 34 10 50 42 33 Mean of all elements = 30.17 The variance of all elements = 215.47 Standard deviation SD = 14.68
