Problem with capitalization in _equal_composition #58
Description
I stumbled over an issue, where I wanted to evaluate two poses. Sometimes the ligands were identified as distinct, even though they are the same. I tracked it down to _equal_composition, which basically computes a sum formula of the ligand. However, it does so in a case sensitive manner. In my case, in one of the AtomArrays, chlorine has the element CL, in the other, it has Cl (the first is read from a PDB the second from an mmCIF).
I'm not sure if this counts as a bug and if this is the right place to open an issue. I could also imagine that this could be addressed during file parsing in biotite. Let me know what you think.
I'd be happy to work on a PR (here or in biotite) if you think the issue should be addressed.
In any case, thank you for the nice library 🙂