I have the following pandas data frame:
import numpy as np
import pandas as pd
timestamps = [1, 14, 30]
data = dict(quantities=[1, 4, 9], e_quantities=[1, 2, 3])
df = pd.DataFrame(data=data, columns=data.keys(), index=timestamps)
which looks like this:
quantities e_quantities
1 1 1
14 4 2
30 9 3
However, the timestamps should run from 1 to 52:
index = pd.RangeIndex(1, 53)
The following line provides the timestamps that are missing:
series_fill = pd.Series(np.nan, index=index.difference(df.index)).sort_index()
How can I get the quantities and e_quantities columns to have NaN values at these missing timestamps?
I've tried:
df = pd.concat([df, series_fill]).sort_index()
but it adds another column (0) and swaps the order of the original data frame:
0 e_quantities quantities
1 NaN 1.0 1.0
2 NaN NaN NaN
3 NaN NaN NaN
Thanks for any help here.