如何检查我的 pandas csv 中是否有任何额外的列？

Question

Currently I am trying to check a csv file if there are certain columns (whether they exist) and also to find out if there are any extra columns (that should not be there) in a certain csv file.

I have put all the required columns into a list and check the list against the columns in the file.

list = ['column 1', 'column 2' , 'column 3']
for column in list:
    if column not in list:
        /execute  action

However, I am unable to find out if any extra columns already exist. For example csv file has 4 columns, and 3 of them is checked against the list.

How do I get the last column to be displayed or shown?

Thanks in advance!

Answer 1

Lets say you have a setup like this, for example:

import pandas as pd 
list = ['column 1', 'column 2' , 'column 3']

csv_file = pd.read_csv('csv_file_here')
for col in csv_file.columns: 
    if col not in list:
        print(col) # The extra column

Answer 2

Try the following code (pythonic approach):

import pandas as pd 
someList = ['column 1', 'column 2' , 'column 3']

df = pd.read_csv('filename.csv')

differenceCols= list(set(df.columns) - set(someList))
print(differenceCols)

for item in differenceCols:
    # perform some action