Python Dataframe 指定多列去重、求差集的方法

 
>>>import pandas as pd 
>>>data={'state':[1,1,2,2,1,2,2],'pop':['a','b','c','d','b','c','d']}
>>> =pd.Data (data) 
>>> 
	pop	state
0	a	1
1	b	1
2	c	2
3	d	2
4	b	1
5	c	2
6	d	2
>>> .drop_duplicates(subset=['pop','state'])
	pop	state
0	a	1
1	b	1
2	c	2
3	d	2

>>>data_a={'state':[1,1,2],'pop':['a','b','c']}
>>>data_b={'state':[1,2,3],'pop':['b','c','d']}
>>>a=pd.Data (data_a)
>>>a 
	pop	state
0	a	1
1	b	1
2	c	2
>>>b=pd.Data (data_b) 
>>>b
	pop	state
0	b	1
1	c	2
2	d	3
>>>a = a.append(b)
>>>a = a.append(b)
>>>result = a.drop_duplicates(subset=['pop','state'],keep=False)
>>>result
	pop	state
0	a	1