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You can use the following methods to select columns in a pandas DataFrame by condition:

**Method 1: Select Columns Where At Least One Row Meets Condition**

#select columns where at least one row has a value greater than 2 df.loc[:, (df > 2).any()]

**Method 2: Select Columns Where All Rows Meet Condition**

#select columns where all rows have a value greater than 2 df.loc[:, (df > 2).all()]

**Method 3: Select Columns Where At Least One Row Meets Multiple Conditions**

#select columns where at least one row has a value between 10 and 15 df.loc[:, ((df>=10) & (df15)).any()]

The following examples show how to use each method with the following pandas DataFrame:

import pandas as pd #create DataFrame df = pd.DataFrame({'apples': [7, 3, 3, 4, 3], 'oranges': [2, 0, 2, 0, 1], 'bananas': [5, 0, 4, 0, 12]}, index=['Farm1', 'Farm2', 'Farm3', 'Farm4', 'Farm5']) #view DataFrame print(df) apples oranges bananas Farm1 7 2 5 Farm2 3 0 0 Farm3 3 2 4 Farm4 4 0 0 Farm5 3 1 12

**Example 1: Select Columns Where At Least One Row Meets Condition**

We can use the following code to select the columns in the DataFrame where at least one row in the column has a value greater than 2:

#select columns where at least one row has a value greater than 2 df.loc[:, (df > 2).any()] apples bananas Farm1 7 5 Farm2 3 0 Farm3 3 4 Farm4 0 0 Farm5 3 12

Notice that the **apples** and **bananas** columns are returned because both of these columns have at least one row with a value greater than 2.

**Example 2: Select Columns Where All Rows Meet Condition**

We can use the following code to select the columns in the DataFrame where every row in the column has a value greater than 2:

#select columns where every row has a value greater than 2 df.loc[:, (df > 2).all()] apples Farm1 7 Farm2 3 Farm3 3 Farm4 4 Farm5 3

Notice that only the **apples** column is returned because it is the only column where every row in the column has a value greater than 2.

**Example 3: Select Columns Where At Least One Row Meets Multiple Conditions**

We can use the following code to select the columns in the DataFrame where at least one row in the column has a value between 10 and 15:

#select columns where every row has a value greater than 2 df.loc[:, ((df>=10) & (df15)).any()] bananas Farm1 5 Farm2 0 Farm3 4 Farm4 0 Farm5 12

Notice that only the **bananas **column is returned because it is the only column where at least one row in the column has a value between 10 and 15.

**Additional Resources**

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

How to Select Columns by Name in Pandas

How to Select Columns by Index in Pandas

How to Select Columns Containing a Specific String in Pandas