pandas dataframe index, column 가져오고 변경하기

pandas dataframe의 index와 column을 가져오고, 변경하는 방법은 아래와 같다

 

 

 

 

 

import numpy as np
import pandas as pd
import sklearn

 

In [3]:

A=np.random.sample(10)*5+2
B=np.random.sample(10)*2+3
C=np.random.sample(10)*3-1
df=pd.DataFrame({'A':A, 'B':B, 'C':C})
df

 

Out[3]:

	A	B	C
0	6.161620	4.609621	-0.186786
1	3.937665	4.936775	0.969055
2	3.882688	4.034569	1.483390
3	5.857642	3.107870	1.665433
4	4.728388	3.322217	-0.494691
5	4.871471	4.859152	0.801952
6	5.742581	4.162347	0.005457
7	5.022636	4.203201	-0.690801
8	6.348671	4.736056	-0.929213
9	2.979743	3.602551	1.888747

 

In [4]:

df.index  # index 정보 가져오기

 

Out[4]:

RangeIndex(start=0, stop=10, step=1)

 

In [5]:

df.columns  # column 정보 가져오기

 

Out[5]:

Index(['A', 'B', 'C'], dtype='object')

 

In [6]:

df.set_index(np.array(range(9,-1,-1))) # index를 변경

 

Out[6]:

	A	B	C
9	6.161620	4.609621	-0.186786
8	3.937665	4.936775	0.969055
7	3.882688	4.034569	1.483390
6	5.857642	3.107870	1.665433
5	4.728388	3.322217	-0.494691
4	4.871471	4.859152	0.801952
3	5.742581	4.162347	0.005457
2	5.022636	4.203201	-0.690801
1	6.348671	4.736056	-0.929213
0	2.979743	3.602551	1.888747

 

In [7]:

df.rename(columns={'A':'Apple','B':'Banana'}) # column 이름 변경

 

Out[7]:

	Apple	Banana	C
0	6.161620	4.609621	-0.186786
1	3.937665	4.936775	0.969055
2	3.882688	4.034569	1.483390
3	5.857642	3.107870	1.665433
4	4.728388	3.322217	-0.494691
5	4.871471	4.859152	0.801952
6	5.742581	4.162347	0.005457
7	5.022636	4.203201	-0.690801
8	6.348671	4.736056	-0.929213
9	2.979743	3.602551	1.888747