Python | Pandas Series.last_valid_index()

Pandas series is a One-dimensional ndarray with axis labels. The labels need not be unique but must be a hashable type. The object supports both integer- and label-based indexing and provides a host of methods for performing operations involving the index.

Pandas Series.last_valid_index() function return index for the last non-NA/null value in the given series object.

Syntax: Series.last_valid_index()

Parameter : None

Returns : scalar

Example #1: Use Series.last_valid_index() function to return the last valid index of the given series object.

# importing pandas as pd
import pandas as pd

# Creating the Series
sr = pd.Series(['New York', 'Chicago', 'Toronto', None, 'Rio'])

# Create the Index
index_ = ['City 1', 'City 2', 'City 3', 'City 4', 'City 5']

# set the index
sr.index = index_

# Print the series
print(sr)

Output :

Now we will use Series.last_valid_index() function to return the last valid index of the given series object.

# return the last valid index
result = sr.last_valid_index()

# Print the result
print(result)

Output :

As we can see in the output, the Series.last_valid_index() function has returned the last valid index in the given series object.

Example #2: Use Series.last_valid_index() function to return the last valid index of the given series object.

# importing pandas as pd
import pandas as pd

# Creating the Series
sr = pd.Series([19.5, 16.8, None, 22.78, 16.8, 20.124, None, None, None])

# Print the series
print(sr)

Output :

Now we will use Series.last_valid_index() function to return the last valid index of the given series object.

# return the last valid index
result = sr.last_valid_index()

# Print the result
print(result)

Output :

As we can see in the output, the Series.last_valid_index() function has returned the last valid index in the given series object.