func int main() {
  matrix a <3, 3>;
  matrix mean_r<3,1>;
  matrix mean_c<1,3>;
  a = [1.1, 1.2, 1.3; 1.0, 1.3, 1.0; 1.0, 1.0, 1.0];
  mean_r = mean_row(a);
  print(mean_r);
  a = [1.1, 1.0, 1.0; 1.2, 1.3, 1.0; 1.3, 1.0, 1.0];
  mean_c = mean_col(a);
  print(mean_c);
  return 0;
}