Hi all, I have the following problem, when I compare the results of a merger tree created using fastBuildMerge.py for the most massive halo at z=0, with the output of running hop manually, I get the following discrepancy: #part x y z fastBuildMerge 33809 0.492 0.495 0.485 Hop(yt)manually 50931 0.5019 0.4981 0.4902 old enzohop 43815 0.5019 0.4981 0.4902 Visual inspection of slices show, that the last two positions are correct. So I wonder why the merger_tree gives wrong values even though it is calling the same Hop routine. I need the positions of the parent halos for profiling, and a difference of 0.01 in position corresponds to 1.28 Mpc which is a lot for a galaxy cluster, and would spoil the analysis. The difference in mass between the first two is strange as well. Did anybody encounter the same problem and/or knows where it is coming from? Thanks! Jean-Claude