Change type of member of a class stored in a tree

[Wile_E_Coyote]

The “Adding Your Class to ROOT: ClassDef” web page contains a bit not-up-to-date informations.
See:

Simple way to create and merge shared libraries?

[quote]as far as I remember, you need “ClassDef” / “ClassImp” macros for a class only if you want to use ROOT I/O on its objects. So, if you do NOT need it, you can remove them (even if the class inherits from TObject).[/quote]Please note that neither ClassDef nor ClassImp is needed to to ROOT I/O. All you need for ROOT I/O is to generate the dictionary for the class. Note that ClassDef provides an optimizations, object with a ClassDef will be smaller on file and will be read slightly faster. …

Adding a class: hand holding requested

I’d just change “.cxx” into “.cc” directly here … and learn the “-p” flag … you will often need it … rootcint -f dictionary.cc -c -p TestClass.hh Root_LinkDef.h Also, as you plan to use “std:: vector”, maybe it would be good to: #include in your “TestClass.hh” file. One more thing. If you ever use “ClassDef”, remember that it must be the last line in your class definition AND it must be PUBLIC: class MyClass { public: // something protected: // something else private: // yet somethi…

See also: ROOT User’s Guide → Adding a Class