Scale a root file event by event

ROOT
1

Dear Experts,

I have a root file, say yyy.root and I want to scale it down event by event 1/6 times and create a new root file with same tree and branches as the previous file.

While plotting a histogram, I know, I have to scale it, something like,
Double_t scale = 1.0/6.0;
hist1=Scale(scale);

I want to do the same thing and write it to a new root file.
Can someone help me!

Thank you in advance,
C.S

ROOT Version: 6.14
Platform: Not Provided
Compiler: Not Provided

2

I guess you just want to scale one value (one branch), right? You have to do it manually: open your file, loop over the entries, scale the value (branch) you wand to scale down, and write the tree to a new file.

3

Hi bellenot,

Thank you for your quick response.
Basically, I want to scale the entire tree (all branches). Is it possible to do so?
Can you please share a sample code, if possible?

Thank you,
C.S

4

Then you have to read all branches, scale all values, and write to another tree. You could get inspiration form the copytree3.C tutorial