df.fillna in python code example

Example 1: python pandas replace nan with null

df.fillna('', inplace=True)

Example 2: dataframe fillna with 0

df['column'] = df['column'].fillna(0)

Example 3: python fillna with mean in a dataframe

df["newColumName"] = df["originalColumnName"].fillna(df["originalColumnName"].mean())

Example 4: df.fillna(-999,inplace=True)

df2.replace(-999, np.nan, inplace=True)
df2.fillna(df2.mean())

    EventId A       B        C
0   100000  0.91    124.711  2.666000
1   100001  0.91    124.711 -0.202838
2   100002  0.91    124.711 -0.202838
3   100003  0.91    124.711 -0.202838

Example 5: fillna pandas inplace

When inplace = True , the data is modified in place, which means it will return nothing and the dataframe is now updated. When inplace = False , which is the default, then the operation is performed and it returns a copy of the object. You then need to save it to something.