Use Operation::Tanh and Operation::Signum instead of manual computing

amdis/gridfunctions/Operations.hpp

@@ -116,7 +116,7 @@ namespace AMDiS
     REQUIRES(Concepts::AnyGridFunction<T>)>
   auto tanh(T&& value)
   {
-    return invokeAtQP([](auto const& v) { using std::tanh; return tanh(v); }, FWD(value));
+    return invokeAtQP(Operation::Tanh{}, FWD(value));
   }
 
   /// \brief Applies \ref Operation::Signum to GridFunctions. \relates ComposerGridFunction
@@ -124,7 +124,7 @@ namespace AMDiS
     REQUIRES(Concepts::AnyGridFunction<T>)>
   auto signum(T&& value)
   {
-    return invokeAtQP([](auto const& v) { return v > 0.0 ? 1.0 : -1.0; }, FWD(value));
+    return invokeAtQP(Operation::Signum{}, FWD(value));
   }
 
   /// \brief Applies \ref Operation::Sqr to GridFunction. \relates ComposerGridFunction