message: Fixed Windows compile issue
diff: @@ -2970,10 +2970,9 @@ public:
  explicit
  PolyFitVisitor(size_type d, weight_func w_func =
  - [](const index_type &, size_type) -> value_type {
  - return (value_type(1));
  - }
  - ) : degree_(d), weights_(w_func) { }
  + [](const I &, std::size_t) -> value_type {
  + return (T(1));
  + }) : degree_(d), weights_(w_func) { }
  private:
  