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How to add missing dates to a Python Pandas dataframe?

Sometimes, we want to add missing dates to a Python Pandas dataframe, we call reindex.

In this article, we’ll look at how to add missing dates to a Python Pandas dataframe, we call reindex..

How to add missing dates to a Python Pandas dataframe?

To add missing dates to a Python Pandas dataframe, we call reindex.

For instance, we write

import pandas as pd

idx = pd.date_range('09-01-2013', '09-30-2013')

s = pd.Series({'09-02-2013': 2,
               '09-03-2013': 10,
               '09-06-2013': 5,
               '09-07-2013': 1})
s.index = pd.DatetimeIndex(s.index)

s = s.reindex(idx, fill_value=0)

to create a series s.

And then we call s.reindex with idx to fill the series s with the date range values.

And any missing values in the series are filled with 0 by setting the fill_value argument to 0.

Posted in Python, Python Answers