Add new BaseMean in the API docs and minor fixes

docs/api.rst

@@ -341,7 +341,7 @@ Template
 .. code-block:: cpp
 
   template <typename Params>
-  struct MeanFunction {
+  struct MeanFunction : public BaseMean<Params> {
     MeanFunction(size_t dim_out = 1) : _dim_out(dim_out) {}
     template <typename GP>
     Eigen::VectorXd operator()(const Eigen::VectorXd& v, const GP&) const

src/limbo/mean/mean.hpp

@@ -59,7 +59,7 @@ namespace limbo {
         */
         template <typename Params>
         struct BaseMean {
-            BaseMean(size_t dim_out = 1) : _dim_out(dim_out) {}
+            BaseMean(size_t dim_out = 1) {}
 
             size_t h_params_size() const { return 0; }
 
@@ -73,9 +73,6 @@ namespace limbo {
                 // This should never be called!
                 assert(false);
             }
-
-        protected:
-            size_t _dim_out;
         };
     } // namespace mean
 } // namespace limbo

src/tutorials/advanced_example.cpp

@@ -112,7 +112,7 @@ Eigen::Vector2d forward_kinematics(const Eigen::VectorXd& x)
 }
 
 template <typename Params>
-struct MeanFWModel {
+struct MeanFWModel : mean::BaseMean<Params> {
     MeanFWModel(size_t dim_out = 1) {}
 
     template <typename GP>