#### CPL 14 – SUM, MEAN AND STANDARD DEVIATION

14. Develop a program using pointers to compute the sum, mean and standard deviation of all elements stored in an array of n real numbers.

Algorithm:

Step 1: [Start]

Step 2: [Input the elements]

Step 3: [Initialize] sum=0,sumstd=0

Step 4: [Compute sum, mean, standard deviation]
Ptr=a
For i = 0 thru n in steps of 1
Sum=sum+*ptr
Ptr++
Mean=sum/n
Ptr=a
For i 0 thru n in steps of 1
Sumstd=sumstd+pow((*ptr-mean),2)
Ptr++
std=sqrt(sumstd/n)

Step 5: [Output]
Print sum, mean, standard deviation

Step 6: [Stop]

FLOWCHART:

PROGRAM:

#include<stdio.h>
#include<math.h>

void main ()
{
float a[20], sum1 = 0, sum2 = 0, mean, var, dev;
int i, n;
printf (“Enter no of elements:”);
scanf (“%d”, &n);
printf (“Enter array elements:”);
for (i = 0; i < n; i++)
{
scanf (“%f”, a + i);
sum1 = sum1 + * (a + i);
}
mean = sum1 / n;
for (i = 0; i < n; i++)
{
sum2 = sum2 + pow ((*(a + i) – mean), 2);
}
var = sum2 / n;
dev = sqrt (var);
printf (“Sum       :%fn”, sum1);
printf (“Mean      :%fn”, mean);
printf (“Variance  :%fn”, var);
printf (“Deviation :%fn”, dev);

}

OUTPUT: