Can TTree::MakeClass() output be used to create a new tree?

ROOT
1

I have a source file generated in the past with TTree::MakeClass(). I know how to use this to reference the contents of an N-tuple file. I would like to know if there is a way to supply this class in order to create a new N-tuple in a ROOT file with the same structure. I currently have a function with a few hundred lines of “tree->Branch(…);” statements for all the variables, and would love to collapse this down to something like “tree->Branches()” (just pseudocode, of course).

Is this possible under ROOT 4.04/02?

2

MakeClass do not really contain the same structure as the original (it is usually a simplified version). Also if your structure was created with a ‘leaflist’, it can now re-created (exactly) with a class.

That’s said you can get a similar tree by simply extracting the data member of the MakeClass that are your data, put them in a simple struct (or class), generate the dictionary for this and create your branch using this new class.

Philippe.