Copy std::vector from one TTree to another

ROOT
7

I found many posts relating to vectors of special C++ objects, but I had trouble finding anything about function templates.

I tried the following:

ROOT.gInterpreter.GenerateDictionary("vector<Int_t>","vector")
ROOT.gInterpreter.GenerateDictionary("vector<Int_t>::assign","vector")
ROOT.gInterpreter.GenerateDictionary("vector::assign","vector")
ROOT.gInterpreter.GenerateDictionary("copy","algorithm")

and other variations with std:: prefixing. The first generates something, but when I then make a ROOT.std.vector(“Int_t”)(), it does not have the assign method. The other trials give error messages.

I have never fully understood the concepts or proper instructions for generating dictionaries in this way. The instructions seem to be mostly clear when referring to vectors and custom classes:
root.cern.ch/drupal/content/how- … dictionary
But I’m not able to “translate” to algorithms, or missing methods for already-known classes.

Jean-François