def METHOD_NAME(self, data):
    data = np.asarray(data)
    if len(data) == 0:
        raise ValueError("Performance data requires at least one line per table!")
    weights = np.asarray(sorted(set(data[:, 0])))
    table = []
    for weight in weights:
        selection = (data[:, 0] == weight)
        table.append(data[selection][:, 1:])
    return weights, table