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I have the following dataset:

import pandas as pd
from pmdarima import auto_arima
url_train_a = 'https://raw.githubusercontent.com/oreilly-mlsec/' + \
'book-resources/master/chapter3/datasets/cpu-utilization/cpu-train-a.csv'
df_train_a = pd.read_csv(url_train_a, parse_dates=[0], infer_datetime_format=True)

And I can see that the column date time was converted to the right format:

df_train_a.head(10)
    datetime            cpu
0   2017-01-27 18:42:00 1.14
1   2017-01-27 18:43:00 1.10
2   2017-01-27 18:44:00 1.09
3   2017-01-27 18:45:00 1.08
4   2017-01-27 18:46:00 1.08
5   2017-01-27 18:47:00 1.08
6   2017-01-27 18:48:00 1.15
7   2017-01-27 18:49:00 1.13
8   2017-01-27 18:50:00 1.09
9   2017-01-27 18:51:00 1.06

But when trying to apply the auto_arima function, I get this error:

stepwise_model = auto_arima(df_train_a, start_p=1, start_q=1,
                           max_p=3, max_q=3, m=12,
                           start_P=0, seasonal=True,
                           d=1, D=1, trace=True,
                           error_action='ignore',  
                           suppress_warnings=True)
TypeError: The DType <class 'numpy.dtype[datetime64]'> could not be promoted by <class 'numpy.dtype[float64]'>. This means that no common DType exists for the given inputs. For example they cannot be stored in a single array unless the dtype is `object`. The full list of DTypes is: (<class 'numpy.dtype[datetime64]'>, <class 'numpy.dtype[float64]'>)

I tried to detect some NaNs (perhaps NaNs should be converted to NaTs) and checked this:

df_train_a[df_train_a['datetime'].isnull()]
# No NaNs detected

df_train_a.describe(datetime_is_numeric=True)
        datetime                        cpu
count   420                             420.000000
mean    2017-01-27 22:11:29.999999744   1.233262
min     2017-01-27 18:42:00             0.570000
25%     2017-01-27 20:26:45             0.787500
50%     2017-01-27 22:11:30             1.110000
75%     2017-01-27 23:56:15             1.582500
max     2017-01-28 01:41:00             2.550000
std     NaN                             0.505668

What I am doing wrong? Is it something with the library?

Alexis
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