Replace None with NaN in pandas dataframe

dataframe, nan, nonetype, pandas, replace

Solution

You can use `DataFrame.fillna` or `Series.fillna` which will replace the Python object `None`, not the string `'None'`.

import pandas as pd
import numpy as np

For dataframe:

df = df.fillna(value=np.nan)

For column or series:

df.mycol.fillna(value=np.nan, inplace=True)

Problem

I have table `x`: ``` website 0 http://www.google.com/ 1 http://www.yahoo.com 2 None ``` I want to replace python None with pandas NaN. I tried: ``` x.replace(to_replace=None, value=np.nan) ``` But I got: ``` TypeError: 'regex' must be a string or a compiled regular expression or a list or dict of strings or regular expressions, you passed a 'bool' ``` How should I go about it?

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