[Biopython] Difference between SVDSuperimposer and PDB.Superimposer

[George Devaniranjan]

Hi,

I would like to calculate the RMSD using biopython, there seems to be
2 functions ( SVDSuperimposer and PDB.Superimposer) I could use, is
there a difference?

Another question I have is if I use the C-alpha carbon of proteins,
does it actually calculate the "real" rmsd, what I mean is -for
instance, PYMOL would "throw away" atoms over several cycles to
improve the RMSD, I don't want to do that--looking at the code I think
bipython does calculate the "real" RMSD, is this correct?

Thank you very much,
George