Pandas: How to Filter Series by Value


You can use the following methods to filter the values in a pandas Series:

Method 1: Filter Values Based on One Condition

#filter for values equal to 7
my_series.loc[lambda x : x == 7]

Method 2: Filter Values Using “OR” Condition

#filter for values less than 10 or greater than 20
my_series.loc[lambda x : (x < 10) | (x > 20)]

Method 3: Filter Values Using “AND” Condition

#filter for values greater than 10 and less than 20
my_series.loc[lambda x : (x > 10) & (x < 20)] 

Method 4: Filter Values Contained in List

#filter for values that are equal to 4, 7, or 23
my_series[my_series.isin([4, 7, 23])]

This tutorial explains how to use each method in practice with the following pandas Series:

import pandas as pd

#create pandas Series
data = pd.Series([4, 7, 7, 12, 19, 23, 25, 30])

#view pandas Series
print(data)

0     4
1     7
2     7
3    12
4    19
5    23
6    25
7    30
dtype: int64

Example 1: Filter Values Based on One Condition

The following code shows how to filter the pandas Series for values equal to 7:

#filter for values equal to 7
data.loc[lambda x : x == 7]

1    7
2    7
dtype: int64

We can also filter for values not equal to 7:

#filter for values not equal to 7
data.loc[lambda x : x != 7]

0     4
3    12
4    19
5    23
6    25
7    30
dtype: int644

Example 2: Filter Values Using “OR” Condition

The following code shows how to filter the pandas Series for values less than 10 or greater than 20:

#filter for values less than 10 or greater than 20
data.loc[lambda x : (x < 10) | (x > 20)]

0     4
1     7
2     7
5    23
6    25
7    30
dtype: int64

Example 3: Filter Values Using “AND” Condition

The following code shows how to filter the pandas Series for values greater than 10 and less than 20:

#filter for values greater than 10 and less than 20
data.loc[lambda x : (x > 10) & (x < 20)]

3    12
4    19
dtype: int64

Example 4: Filter Values Contained in List

The following code shows how to filter the pandas Series for values that are contained in a list:

#filter for values that are equal to 4, 7, or 23
data[data.isin([4, 7, 23])]

0     4
1     7
2     7
5    23
dtype: int64

Additional Resources

The following tutorials explain how to perform other common filtering operations in Python:

How to Filter Pandas DataFrame Rows that Contain a Specific String
How to Filter a Pandas DataFrame on Multiple Conditions
How to Use “NOT IN” Filter in Pandas DataFrame

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