Pandas pop last row

Question

Is there any way to get and remove last row like pop method of python native list?

I know I can do like below. I just want to make it one line.

df.ix[df.index[-1]]
df = df[:-1]

Answer 1

Suppose sample dataframe:

In[51]:df
Out[51]: 
   a  b
0  1  5
1  2  6
2  3  7
3  4  8

you can do using df.drop:

In[52]:df,last_row=df.drop(df.tail(1).index),df.tail(1)

In[53]:df
Out[53]: 
   0  1
0  1  5
1  2  6
2  3  7

In[54]:last_row
Out[54]: 
   a  b
3  4  8

or using numpy as np:

df,last_row=pd.Dataframe(np.delete(df.values,(-1),axis=0)),df.tail(1)

Answer 2

I tested two ways to do this: df = df[: -1] and df = df.drop(df.index[-1]). The first one is much more efficient

Here is the test with 3000 rows.

from datetime import datetime
start = datetime.now()
while df.shape[0] > 1:
    df = df.drop(df.index[-1])
print(datetime.now() - start)

result: 0:00:01.558176

and, df = df.drop(df.index[-1])

from datetime import datetime
start = datetime.now()
while prices.shape[0] > 1:
    prices = prices[: -1]
print(datetime.now() - start)

result: 0:00:00.337987