"ValueError: labels ['timestamp'] not contained in axis" error

Question

I have this code ,i want to remove the column 'timestamp' from the file :u.data but can't.It shows the error
"ValueError: labels ['timestamp'] not contained in axis" How can i correct it

import numpy as np
import pandas as pd
import matplotlib.pyplot as plt 
plt.rc("font", size=14)
from sklearn.linear_model import LinearRegression
from sklearn.linear_model import Ridge
from sklearn.cross_validation import KFold
from sklearn.cross_validation import train_test_split



data = pd.read_table('u.data')
data.columns=['userID', 'itemID','rating', 'timestamp']
data.drop('timestamp', axis=1)


N = len(data)
print data.shape
print list(data.columns)
print data.head(10)

Answer 1

One of the biggest problem that one faces and that undergoes unnoticed is that in the u.data file while inserting headers the separation should be exactly the same as the separation between a row of data. For example if a tab is used to separate a tuple then you should not use spaces.

In your u.data file add headers and separate them exactly with as many whitespaces as were used between the items of a row. PS: Use sublime text, notepad/notepad++ does not work sometimes.