I was able to write a function in python to give us a list of subhalos at z=0 with a given mass and this function gives us what I believe is the subhalo ID and I was wondering if there is an easy way to determine what merger tree file (tree_extended.(num).hdf5) this subhalo's merger tree would be located in so that we can read that file and manipulate the data in its merger tree. Thanks!
This is done in the example scripts in order to load the tree of a given subhalo, specifically in this treeOffsets function. You should be able to adapt it to what you need. In particular, the second part "load groupcat chunk offsets from header of first file".