Dear @bvonhall, @pkonopka and other experts,
We would like to use vectors of struct in the trending of the TPC, as we want to look at different sectors/pads and/or different numbers of subranges of histograms (called a slice).
We managed to have the outcome of the reductor as a vector in the trending tree, but we encounter now an odd behaviour when it comes to the drawing of the trending.
Currently, we are saving the trending tree into this ROOT file. The provided example contains the trending of the pseudorapidity distribution sliced into different ranges (in this case positive and negative ranges). For each of these two slices, we calculate the relevant quantities (e.g. mean x, stddev x), save them in one struct per slice and push this struct into the vector. So each vector entry corresponds to one slice of the histogram which we want to trend. After retrieving the statistical quantities per slice, we want to draw one trending histogram per slice via the TTree Draw function.
Our current investigation found that the code runs until the call of the Draw function (i.e. the vector of structs is saved properly in the tree). We tried to investigate whether the draw function does not support the vector of structs, so we tried its execution in the command line of the terminal using TestTPCTH1Slicer->Draw("hEtaRatio[0].meanX:time","","L*")
. With this, we want to plot the mean x of the first slice of the Eta distribution as a function of time given the treeTest.root file mentioned above.
Now, the weird issue concerns the environment where this is executed: in a normal ROOT6 environment (ROOT6-24), as well as in recent O2Physics, O2 and AliPhysics environments, this commands works as it should.
However, when used in QC environment (recently updated), this commands fails with the error in the log. However, if the code is executed immediately after the first crash, the command again works as expected.
We tried to investigate this issue with @wiechula and @sheckel, but without success. We would therefore ask if someone already encountered something similar, or had an idea of what is going on?
Thanks a lot in advance for any input/suggestion,
Cheers.
Cindy and Marcel