def getTrivialMatch(ach, bch):
    """Returns lists of matching residues (match based on residue number).

    """
    amatch = []
    bmatch = []
    match = 0.0
    for ares in ach:
        bres = bch[ares.getResnum(), ares.getIcode()]
        if bres is not None:
            if ares.getResname() == bres.getResname():
                match += 1
            amatch.append(ares.getResidue())
            bmatch.append(bres.getResidue())
    return amatch, bmatch, match
