Mean of a branch in a tree , graph

Hi Rooters,

I have a tree containing 2 branches : A and mult. A is A[2] and mult is int.
There are several times the same value of A in a root file but with different value mult. For example, it can have 100 000 entries but only 40 differents values of A (80,81,82,83,…101,102,103 …).
For each A there is a mult :
A=96 and mult = 3
A=100 and mult =5
A=96 and mult = 4
A=95 and mult = 2
A = 100 and mult =6

When I type ,

t->Draw(“mult : A”)

, it draws all values of mult for all values A. I would like to draw the mean value of mult for each different value of A. How can I make that?

Thanks

you already posted this message in support (see answer there)

Rene