On Thu, 6 Mar 2003, Rene Brun wrote: >Hi Carlos, > >Instead of using the "conventional" Event-like class, >with hardwired data members, I recommend a dynamic collection of TObject*. >This is much more flexible. One can easily add a new object or collection >to the list of collections for the Event. Thank you for your answer, Rene. However, avoiding the use of classes is not always an easy solution, as they usually contain many methods operating on their data members which are needed for the analysis. I could add a new data member which is a dynamic collection of all the others and create a branch with this one. But this is not very different from manual splitting, especially because the automatic splitting works to full degree if the members of the collection are themselves collections. Creating this kind of collections of collections for all members of all classes in order to allow an automatic splitting can be tedious. Being able to use C++ classes and all their advantages (data members + methods) and at the same time being able to stream data members succesfully would be interesting. It looks to be a very general problem. Carlos > >TTree has several Branch constructors. Look at the following: >TTree::Branch(TCollection *list, Int_t bufsize, Int_t splitlevel, const >char *name) > >This constructor answers your problem/question. see the documentation >of this class that includes an example of use. > http://root.cern.ch/root/htmldoc/src/TTree.cxx.html#TTree:Branch > >Rene Brun > > >On Thu, 6 Mar 2003, >Carlos Muņoz Camacho wrote: > >> >> Hi, >> >> Consider a class TEvent containing a pointer to an object >> TDetectorAEvent, which contains itself TClonesArrays and some other >> objects. Everything inherit from TObject. If we write a tree with a TEvent >> in a branch and set maximum splitting, TDetectorAEvent will not split >> because it is not an object itself but a pointer (and even if it is an >> object only splits one level). This behaviour is documented. Only pointers >> to TClonesArray work. The workarounds I can think of are: >> >> 1.- Manual splitting of TEvent, which may be extremely tedious if TEvent >> contains many data members. >> >> 2.- Remove the pointer to the object and use an object itself. This allows >> at least one level of splitting, but having objects themselves and not >> pointers does not allow dynamic allocation. >> >> Are there any other, more interesting, solutions ? Will splitting of >> pointers to TObjects be supported in a near future ? Thanks! >> >> ROOT 3.03/08 in RedHat 7.2 >> >> Carlos Muņoz >> SPhN/CEA-Saclay >>
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