Ejemplo n.º 1
0
void normalize(vnl_matrix<double>& x,
    vnl_vector<double>& centroid, double& scale) {
  int n = x.rows();
  if (n==0) return;
  int d = x.cols();
  centroid.set_size(d);

  vnl_vector<double> col;
  for (int i = 0; i < d; ++i) {
    col = x.get_column(i);
    centroid(i) = col.mean();
  }
  for (int i = 0; i < n; ++i) {
    x.set_row(i, x.get_row(i) - centroid);
  }
  scale = x.frobenius_norm() / sqrt(double(n));
  x = x / scale;
}