Thread: Any Smart guy can figure this out? Should be simple problem.

I am getting this error when want to compile.

Code:

/tmp/ccmvPe9e.o: In function `stdData':
problem.c:(.text+0x56b): undefined reference to `sqrt'
collect2: ld returned 1 exit status

And this is the "StdDate" below. Where is the problem? sqrt???

Code:

double stdData (double x[], int n)/* function to find the standard deviation */


{
        int i;


        double sum = 0, sum1 = 0;


        double sum2, std;


        for (i=0; i<n; i++){


                sum1 = sum1 + (x[i]*x[i]);


                sum = sum + x[i];


        }


        sum2 = (sum * sum)/(n*n);


        std = sqrt(sum1- sum2);


        return (std);


}