diff --git a/dune/gfe/localgeodesicfefunction.hh b/dune/gfe/localgeodesicfefunction.hh
index 56a565551cec87155291042c6e41d7faffd27c17..f91496bc707f72172d834d16a83a26377b85229c 100644
--- a/dune/gfe/localgeodesicfefunction.hh
+++ b/dune/gfe/localgeodesicfefunction.hh
@@ -74,7 +74,9 @@ public:
     /** \brief Constructor */
     LocalGeodesicFEFunction(const std::vector<TargetSpace>& coefficients)
         : coefficients_(coefficients)
-    {}
+    {
+        assert(coefficients_.size() == dim+1);
+    }
 
     /** \brief Evaluate the function */
     TargetSpace evaluate(const Dune::FieldVector<ctype, dim>& local) const;