Корреляция функции с 10 переменными

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double corr(double* a, double* b){
  double sum_x = 0;
  double sum_y = 0;
  double sum_xy = 0;
  double sum_xsq = 0;
  double sum_ysq = 0;
  for(int i = 0; i < 10; i++){
    sum_x += a[i];
    sum_y += b[i];
    sum_xy += a[i] * b[i];
    sum_xsq += a[i] * a[i];
    sum_ysq += b[i] * b[i];
  }
  return (10 * sum_xy - sum_x * sum_y) / sqrt((10 * sum_xsq - sum_x * sum_x) * (10 * sum_ysq - sum_y * sum_y));
}