extern real fit_ahx(int nres, t_bb bb[], int natoms, int nall, atom_id allindex[],
rvec x[], int nca, atom_id caindex[], gmx_bool bFit);
extern real fit_ahx(int nres, t_bb bb[], int natoms, int nall, atom_id allindex[],
rvec x[], int nca, atom_id caindex[], gmx_bool bFit);