# Write a C program to implement the `linear regression algorithm`.

#### Algorithm:

```Step 1.  Read n
Step 2.  sumx = 0
Step 3.  sumxsq = 0
Step 4.  sumy = 0
Step 5.  sumxy = 0
Step 6.  for i = 1 to n do
Step 8.  sumx = sumx + x
Step 9.  sumxsq = Sumxsq + x2
Step 10. sumy = Sumy + y
Step 11. sumxy = sumxy + x * y end for
Step 12. denom = n * sumxsq – sumx * sumx
Step 13. a0 = (sumy * sumxsq – sumx * sumxy) / denom
Step 14. a1 = (n * sumxy - sumx * sumy) / denonm
Step 15. Write a1, a0
Step 16. Stop```

#### Flowchart: #### Program:

```#include<stdio.h>
#include<math.h>
main()
{
int n,I;
float sumx, sumxsq, sumy, sumxy, x, y, a0, a1, denom;
printf(“enter the n value”);
scanf(“%d”, &n);
sumx = 0;
sumsq = 0;
sumy = 0;
sumxy = 0;
for(i = 0; i < n; i++)
{
scanf(“%f %f”, &x, &y);
sumx += x;
sumsq += pow(x, 2);
sumy += y;
sumxy += x * y;
}
denom = n * sumxsq – pow(sumx, 2);
a0 = (sumy * sumxsq – sumx * sumxy) / denom;
a1 = (n * sumxy – sumx * sumy) / denom;
printf(“y = %fx + %f”,a1, a0);
}```

#### Input & Output:

```enter the n value 7
1 2
2 5
4 7
5 10
6 12
8 15
9 19
Y = 1.980769x + 0.096154```
• Updated
Oct 21, 2014
• Views
34,075
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