scalar_t **_cluster_means, **_cluster_var;
scalar_t distance_to_centroid(scalar_t *x, int k);
void initialize_clusters(int nb_points, scalar_t **points);
scalar_t **_cluster_means, **_cluster_var;
scalar_t distance_to_centroid(scalar_t *x, int k);
void initialize_clusters(int nb_points, scalar_t **points);