Pyroot function to create a TTree with Raw data

General Chat
1

I have created this function in pyroot turn my raw data into a ROOT Tree. ChanNames is a list with all the channels available in my detector. I dont know why but I am only saving the real data from the first event in the first channel. In the rest, the branches for each channel are filled with zeros or with a constant value. Not the real data. I don’t what could be wrong

def create_tree(filepath, chanNames, det,nevents):
    myreader = rawio.RawDataReader(filepath)
    events = myreader.read_events(output_format = 2,
                                  skip_empty = True,
                                  nb_events = nevents,
                                  #dump_nums=[1,2,3,4,5,6,7,8,9,10],
                                  trigger_types = [1],
                                  detector_nums = [det],
                                  channel_names = chanNames)

    sampling_interval = 1./625.

    t = TTree('content_events', '')
    baseline = {}
    std_bl = {}
    bcontent={}
    for chan in chanNames:

        # Defining the TTree branches using python arrays of length = 1
        bcontent[chan]=array('f', [0.0])
        baseline[chan] = array('f', [0.0])
        std_bl[chan] = array('f', [0.0])
        
        t.Branch('bcontent_'+chan, bcontent[chan],'bcontent_'+chan+'\F') 
    print('Start!')
    print('')
    for id in range(len(events)):
        if id%1000 == 0 and id > 0:
            print('Event', id)
        traces = events[id]['Z'+str(det)]

        for chan in chanNames:

            # Filling the "baseline" and "std_bl" lists
            bl = []
            time = np.arange(0, len(traces[chan])*sampling_interval, sampling_interval)
            i=0
            bcontent[chan][0]=0
            while time[i] <= 23:
                i+=1
                bl.append(traces[chan][i])   
            baseline[chan][0] = float(np.mean(bl))
            std_bl[chan][0] = float(np.std(bl))
            #print(chan+' baseline= ', baseline[chan][0])
            for j in range(len(time)):
                bcontent[chan][0]=float(traces[chan][j]-baseline[chan][0])
                t.Fill()

    f = TFile('content_events.root', 'recreate')
    t.Write()
    
            
    return f
2

may be @pcanal and @vpadulan can help ?

3

In the meantime, a couple of observations:
1 - Make sure that the values you are passing to the tree are what you expect, i.e., print bcontent[chan][0] just before doing t.Fill() and see if it looks ok.
2 - You should only do t.Fill() once per event, filling values for all branches (chan) at once. Now you are filling in a loop inside another loop over the branches, so if you have e.g. 5 branches, the tree has 5*(Nevents) entries, instead of Nevents (and since chan is not changing in the Fill loop, the branches that are not changing in that loop just keep filling with their last entry value).

4

Dear @RAFALPZN ,

Thanks for reaching out to the forum! Let me stres this point in particular by @dastudillo which is very important

Once you report back after fixing this we can analyse your situation in more detail.

Also, out of curiosity:

        bcontent[chan]=array('f', [0.0])
        baseline[chan] = array('f', [0.0])
        std_bl[chan] = array('f', [0.0])
        
        t.Branch('bcontent_'+chan, bcontent[chan],'bcontent_'+chan+'\F')

Here it looks like you are preparing for three branches, but you only call t.Branch once, is this intentional?

Cheers,
Vincenzo