ValueError: Grouper для «xxxx» не является одномерным

Для следующего ввода кода

cyclestrain = train.groupby('Unit', as_index=True)['cycles'].max()
cyclestest = test.groupby('Unit', as_index=True)['cycles'].max()

Я получаю эту ошибку:

File "D:/FH-Sudwestfalen/CMAPSS_Aircraft_Data/predict-remaining-useful-life-master/neuralnetwork.py", line 57, in cyclestrain = train.groupby('Unit', as_index=True)['cycles'].max()

File "C:\Users\nvidh\Anaconda3\lib\site-packages\pandas\core\generic.py", line 6665, in groupby observed=observed, **kwargs)

File "C:\Users\nvidh\Anaconda3\lib\site-packages\pandas\core\groupby\groupby.py", line 2152, in groupby return klass(obj, by, **kwds) File "C:\Users\nvidh\Anaconda3\lib\site-packages\pandas\core\groupby\groupby.py", line 599, in init mutated=self.mutated)

File "C:\Users\nvidh\Anaconda3\lib\site-packages\pandas\core\groupby\groupby.py", line 3315, in _get_grouper if not isinstance(gpr, Grouping) else gpr

File "C:\Users\nvidh\Anaconda3\lib\site-packages\pandas\core\groupby\groupby.py", line 3025, in init raise ValueError("Grouper for '%s' not 1-dimensional" % t)

ValueError: Grouper for 'Unit' not 1-dimensional