df.fillna(method='pad') code example

Example 1: dataframe fillna with 0

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

Example 2: python pandas fillna

# importing pandas module
import pandas as pd  
# making data frame from csv file
nba = pd.read_csv("nba.csv")
  
# replacing na values in college with No college
nba["College"].fillna("No College", inplace = True)
# OR
nba.College.fillna("No College", inplace = True)
  
print(nba)

Example 3: 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.

Example 4: DataFrame.fillna

>>> df.fillna(0)
    A   B   C   D
0   0.0 2.0 0.0 0
1   3.0 4.0 0.0 1
2   0.0 0.0 0.0 5
3   0.0 3.0 0.0 4