='datetime64[ns]', freq='D')
In [7]: df = pd.DataFrame(np.random.randn(6, 4), index=dates, columns=list...02', '2013-01-03', '2013-01-04',
'2013-01-05', '2013-01-06'],
dtype='datetime64[ns]', freq='D')
In...-03-13', '2012-03-14', '2012-03-15', '2012-03-16',
'2012-03-16'],
dtype='datetime64[ns]', freq=None...='datetime64[ns]', freq='D')
In [7]: df = pd.DataFrame(np.random.randn(6, 4), index=dates, columns=list...时,图形将会使用plot()显示。