nma(...)nma.pdb, or nma.pdbs. This will minimally include an
    object of class pdb as obtained from function
    read.pdb. Alternatively, an object of class pdbsnma is a generic function calling the corresponding function
  determined by the class of the input argument x. Use
  methods("nma") to get all the methods for nma
  generic:  nma.pdb will be used when x is of class
  pdb as obtained from function read.pdb.
  nma.pdbs will perform pdbs object.
  
  See documentation and examples for each corresponding function for
  more details.
nma.pdb, nma.pdbs,
  pca.