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pandasmultiple-columnsdropisin

How do I drop every column that only contains values from a list pandas

I want to be able to drop all columns that only have values from the list that I pass in.

list_of_drops = ['A','B']
d ={'C1':['A','A','A','B','B','B'],
    'C2':['A','C','A','A','A','A'],
    'C3':['A','B','B','A','B','B'],
    'C4':['A','A','A','A','A','A'],
    'C5':['A','A','B','AC','A','B'],
    'C6':['A','A','AD','A','B','A']}

df = pd.DataFrame (d, columns = ['C1','C2','C3','C4','C5','C6'])

In this example, I want to create a dataframe that only has C1, C3, and C4.

Solution

  • To get rid of columns with just one value:

    df= df.loc[:, (df != 'A').any(axis=0)]

    To get rid of columns with only values from a list:

    df= df.loc[:, (~df.isin(list_of_drops)).any(axis=0)]