message: code review: no need of double braces
diff: @@ -113,11 +113,11 @@ std::vector<std::vector<double>> subsampling_sparsify_points_from_file(const std
  #else
  // ------ sparsify_point_set ------
  std::vector<std::vector<double>> subsampling_sparsify_points(const std::vector<std::vector<double>>&, double) {
  - return std::vector<std::vector<double>>{{}};
  + return std::vector<std::vector<double>>{};
  }
  std::vector<std::vector<double>> subsampling_sparsify_points_from_file(const std::string&, double) {
  - return std::vector<std::vector<double>>{{}};
  + return std::vector<std::vector<double>>{};
  }
  #endif
  