Pandas - drop function

Question

I want to drop rows from a dataframe, based on the condition that the value of a specific column is in a list. If this is not the case I want the row to be dropped.

Do you have any suggestions? Thanks in advance

As an example, if the value in column 'C' is not inside the list l, I want to drop the entire row

import pandas as pd
import numpy as np
df = pd.DataFrame(np.random.randint(0,100,size=(20, 4)), columns=list('ABCD'))

l = [4, 6, 23, 45, 79]

Answer 1

df = df[df.apply(lambda x: any(x.isin(l)), axis=1)]

if only one column must be

and if, only C:

df[df.apply(lambda x: x["C"] in l, axis=1)]

or, if all columns:

df = df[df.apply(lambda x: all(x.isin(l)), axis=1)]

Answer 2

You can try like this:

df = pd.DataFrame([[1, 2], [3, 4], [5, 6]], columns=["a", "b"])

df[(df.a.isin([3]) == False)]

This will only leave those lines in the data frame, whose a-value is not in the list given to isin, i.e. that where it is not 3.