Pass-by-value of Eigen matrix (#40)

elsa/core/DataHandlerCPU.cpp

@@ -13,7 +13,7 @@ namespace elsa
     }
 
     template <typename data_t>
-    DataHandlerCPU<data_t>::DataHandlerCPU(DataVector_t vector)
+    DataHandlerCPU<data_t>::DataHandlerCPU(DataVector_t const& vector)
         : _data{std::make_shared<DataVector_t>(vector)}
     {
     }

elsa/core/DataHandlerCPU.h

@@ -78,7 +78,7 @@ namespace elsa
          *
          * \param[in] vector that is used for initializing the data
          */
-        explicit DataHandlerCPU(DataVector_t vector);
+        explicit DataHandlerCPU(DataVector_t const& vector);
 
         /// copy constructor
         DataHandlerCPU(const DataHandlerCPU<data_t>& other);