Error In Gapfilling By Row In Pandas

2015 2016 2017 2018 2019 2020 2021 2022 2023 2024 2025 0.4818 0.8109 0.9031 I have

Solution 1:

The error you're getting implies that your DataFrame has mixed types - perhaps you have integer columns as well as floating columns.

In any case, dropping the inplace argument should allow fillna to work across rows:

df.fillna(axis=1, method='ffill')