def reduced_display(_components):
    """Reduced display for quick view of the data structure. The method shows the
    first and the last two data values.
    """
    _string = []
    for _, item in enumerate(_components):
        temp = item.ravel()
        lst = [str(temp[0]), str(temp[1]), str(temp[-2]), str(temp[-1])]
        _string.append([("{0}, {1}, ..., {2}, {3}").format(*lst)])
    return _string