def selection_strategy(oasis_obj, strategy='spectral-oasis', nsel=1, neig=None):
    """ Factory for selection strategy object

    Returns
    -------
    selstr : SelectionStrategy
        Selection strategy object

    """
    strategy = strategy.lower()
    if strategy == 'random':
        return SelectionStrategyRandom(oasis_obj, strategy, nsel=nsel, neig=neig)
    elif strategy == 'oasis':
        return SelectionStrategyOasis(oasis_obj, strategy, nsel=nsel, neig=neig)
    elif strategy == 'spectral-oasis':
        return SelectionStrategySpectralOasis(oasis_obj, strategy, nsel=nsel, neig=neig)
    else:
        raise ValueError('Selected strategy is unknown: '+str(strategy))
Factory for selection strategy object

    Returns
    -------
    selstr : SelectionStrategy
        Selection strategy object