Splitting a tree


I would like to know if there is a simple way of splitting a tree into two other new trees.
For example:

I have a tree “old” with n branches and 10 events (rows). I want two new trees ("tree1"and “tree2”) as follows:

tree1 with the first 7 events and all branches of old.
tree2 with the last 3 events and all branches of old.

I was also wondering if I can make other types of selections (some selected events and branches) in an easy way, like it was a matrix with column as branches and line as events.


see TTRee::CopyTree, CloneTree and tutorials copytree*