Hi everybody
I have a problem with TTree. I’m trying to read the data from file, when the data are only number all ok, but if 1 column is string I have a problem, not to read it but when I plot. Following the piece of code in pyroot:
tree= TTree ("tree","tree") #creeate TTree
tree.ReadFile(input_file,"source/C:HV:HV_err:R:R_err",'\t') # read data from file
N=tree.Draw("HV:R:HV_err:R_err","","goff")
gr = TGraphErrors(N,tree.GetV1(),tree.GetV2(),tree.GetV3(),tree.GetV4())
gr.Draw( 'AP' )
The output is always a plot with line but not with the data in the file (always the same line), why this?? (if I remove the string column work!)