How to replace Null values using Pandas
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The Pandas library will give you the tools to replace the Null values the same way as replacing NaN values.
Fillna
The .fillna() method will replace all Null values in contained in a pandas.Series ou pandas.DataFrame.
The method takes multiple arguments such as
Value
The value you want to replace the Null with.
Method
The method of fill. Can be forward fill as "ffill", backward fill as "bfill".
Axis
The axis you want to perform the operation on, it works only when given a DataFrame.
An example on a Serie
# My column is the column in which
# we want to replace our Null
df["my_column"] = df["my_column"].fillna(0)
An example on a DataFrame
# Here we apply the method on a dataframe itself
df = df.fillna(0) # Here axis 1 means columns
Here you are, you know how to replace your Null by a specific value !
If you want to learn more about Backfill or Forward Fill, you can check the links below


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