[Python] Scikit-Learn Linear Regression using Datetime Values and forecasting

Below is a sample of the dataset.

row_id datetime energy
1 2008-03-01 00:00:00 1259.985563
2 2008-03-01 01:00:00 1095.541500
3 2008-03-01 02:00:00 1056.247500
4 2008-03-01 03:00:00 1034.742000
5 2008-03-01 04:00:00 1026.334500

The dataset has datetime values and energy consumption for that hour in object and float64 dtypes. I want to predict the energy using the datetime column as the single feature.

I used the following code

train['datetime'] = pd.to_datetime(train['datetime'])
X = train.iloc[:,0]
y = train.iloc[:,-1]


I could not pass the single feature as Series to the fit object as I got the following error.

ValueError: Expected 2D array, got 1D array instead:
array=['2008-03-01T00:00:00.000000000' '2008-03-01T01:00:00.000000000'
'2008-03-01T02:00:00.000000000' ... '2018-12-31T21:00:00.000000000'
'2018-12-31T22:00:00.000000000' '2018-12-31T23:00:00.000000000'].
Reshape your data either using array.reshape(-1, 1) if your data has a single feature or
array.reshape(1, -1) if it contains a single sample.


So I converted their shapes as suggested.

X = np.array(X).reshape(-1,1)
y = np.array(y).reshape(-1,1)

from sklearn.linear_model import LinearRegression
model_1 = LinearRegression()
model_1.fit(X,y)

test = pd.to_datetime(test['datetime'])
test = np.array(test).reshape(-1,1)

predictions = model_1.predict(test)


The LinearRegression object fitted the feature X and target y without raising any error. But when I passed the test data to the predict method, it threw the following error.

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 can't wrap my head around this error. How can I use the datetime values as a single feature and apply simple linear regression to predict the target value and do TimeSeries forecasting? Where am I doing wrong?

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