It does not matter. rmsd is going to give you a number no matter if the molecules are aligned or not. The thing is how you interpret the number, so discussing about alignment does not apply for implementation, only for interpretation. Correspondence does apply. If not addressed, fine with me :)


Correspondence and rigid alignment are different questions.
Correspondence is hard enough to solve that I figured it was clearly
not being solved. Rigid alignment is trivial so it is not unreasonable
to assume it is done (but unclear whether or not it is).
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