How to Drop Multiple Columns By Conditional Index Value

Question

How do you drop multiple columns by a conditional index value? For example, I'd like to drop all columns that are greater than index number 40.

Franklin Ayala · Accepted Answer · 2021-12-16 03:52:24Z

1

Assuming that you have a DataFrame like this:

df = pd.DataFrame(np.arange(120).reshape(60, 2),
                  columns=['A', 'B'])

You can drop the columns when the index is greater than a specified value (for instance 40):

value=40
rows_to_drop=df.index[np.where(df.index>value)[0]]
df=df.drop(rows_to_drop,axis=0)

df now has the columns that have an index less than 40.

I hope I have understood your question.

answered Dec 16, 2021 at 3:52

Franklin Ayala

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