pandas versions code example

Example 1: pandas

#for dropping a column in a dataframe
df = df.drop(['PassengerId'], axis = 1)

#for selecting all columns except one
df.iloc[:, df.columns != "Survived"]

#for checking nan values is a column
df['your column name'].isnull()

Example 2: pandas

df = pd.DataFrame(np.random.randn(1000, 4), index=ts.index,
   .....:                   columns=['A', 'B', 'C', 'D'])
   .....: 

In [137]: df = df.cumsum()

In [138]: plt.figure()
Out[138]: <Figure size 640x480 with 0 Axes>

In [139]: df.plot()
Out[139]: <matplotlib.axes._subplots.AxesSubplot at 0x7f53723daa10>

In [140]: plt.legend(loc='best')
Out[140]: <matplotlib.legend.Legend at 0x7f5369d93dd0>