Apologies if this is too basic a question, but I am confused about how ROOT works in the following case. I have an array,
here ‘vec’ is a struct I defined holding an array of 3 long doubles, and n_configs=10000, n_par1=8 are unsigned integers defined at compile time.
I wanted to fill this array with values from a TTreeReader, which worked absolutely fine. However, when I tried to add a third dimension to my array, i.e. filling
where n_par2=5 is also known at compile time, then my code crashed with a segmentation error. After some experimentation it turned out that it ran fine when n_configs was small (e.g. 1000 or so), crashed about half the time when n_configs was around 3000, and crashed all the time when n_configs was more than 8000.
I have no idea what could be causing this behaviour; my only guess is that there is a problem with using TTreeReader to copy data into large arrays.
So is this the case? Is there a limit to the size/dimensions of an array into which data can be copied from a TTreeReader? And if so, is there any workaround?
ROOT Version: 6.20/02
Platform: Linux (Ubuntu 20.04)
Compiler: g++ v9.3.0