[convergence-study] let run() return all computed data

dune/xt/common/convergence-study.cc

@@ -146,7 +146,8 @@ void ConvergenceStudy::print_eoc(std::ostream& out,
   }
 } // ... print_eoc(...)
 
-void ConvergenceStudy::run(const std::vector<std::string>& only_these, std::ostream& out)
+std::map<std::string, std::map<std::string, std::map<size_t, double>>>
+ConvergenceStudy::run(const std::vector<std::string>& only_these, std::ostream& out)
 {
   auto& self = *this;
   // check what we want to compute and print
@@ -340,6 +341,13 @@ void ConvergenceStudy::run(const std::vector<std::string>& only_these, std::ostr
       out << delim;
     out << std::endl;
   }
+  // convert data
+  std::map<std::string, std::map<std::string, std::map<size_t, double>>> return_data;
+  for (const auto& level : data)
+    for (const auto& category : level.second)
+      for (const auto& type : category.second)
+        return_data[category.first][type.first][level.first] = type.second;
+  return return_data;
 } // ... run(...)
 
 

dune/xt/common/convergence-study.hh

@@ -138,7 +138,16 @@ protected:
                  const std::string& target_id) const;
 
 public:
-  void run(const std::vector<std::string>& only_these = {}, std::ostream& out = std::cout);
+  /**
+   * \brief Runs the study and displays a table with all targets, norms, estimates and quantities given by the study
+   *        (if only_these is empty) or only those which are contained in only_these (else).
+   *
+   * \return data with data[foo][bar][level] where 0 <= level <= num_refinements(), "foo" is one of
+   *         {"target", "norm", "estimate", "quantity"} and bar is one of targets(), norms(), estimates() or
+   *         quantities() (intersected with only_these), respectively.
+   **/
+  std::map<std::string, std::map<std::string, std::map<size_t, double>>>
+  run(const std::vector<std::string>& only_these = {}, std::ostream& out = std::cout);
 }; // class ConvergenceStudy