def isdmap(dmethod):
    """Return ``isdmap`` argument for ``.IterStatsConfig`` initialiser.
    """
    if dmethod == 'fista':
        isd = {'Cnstr': 'Cnstr', 'D_F_Btrack': 'F_Btrack', 'D_Q_Btrack':
            'Q_Btrack', 'D_ItBt': 'IterBTrack', 'D_L': 'L', 'D_Rsdl': 'Rsdl'}
    else:
        isd = {'Cnstr': 'Cnstr', 'DPrRsdl': 'PrimalRsdl', 'DDlRsdl':
            'DualRsdl', 'DRho': 'Rho'}
    return isd
