array, I/O file and standard deviation (c++)
- by JohnWong
double s_deviation(double data[],int cnt, double mean)
{
int i;
double sum= 0;
double sdeviation;
double x;
//x = mean(billy,a_size);
for(i=0; i<cnt; i++)
{
sum += ((data[i]) - (mean));
}
sdeviation = sqrt(sum/((double)cnt));
return sdeviation;
}
When I cout the result from this function, it gave me NaN.
I tested the value of (mean) and data[i] using
return data[i] and return mean
they are valid.
when i replaced mean with an actual number, the operation returned a finite number.
but with mean as a variable, it produced NaH.
I can't see anything wrong with my code at the moment.
Again, I am sure mean, data are getting the right number based on those tests.
Thank you
