你可以
merge
按列名称和索引
pandas 0.23.0+
以下内容:
print (df.merge(s.to_frame(), on=['id1','id2','date']))
样品
以下内容:
df = pd.DataFrame({'date':pd.date_range('2015-01-01', periods=6),
'id1':[4,5,4,5,5,4],
'id2':[7,8,9,4,2,3],
'F':list('aaabbb')}).set_index(['id1','id2','date'])
print (df)
F
id1 id2 date
4 7 2015-01-01 a
5 8 2015-01-02 a
4 9 2015-01-03 a
5 4 2015-01-04 b
2 2015-01-05 b
4 3 2015-01-06 b
s = pd.DataFrame({'date':pd.date_range('2015-01-01', periods=3),
'id1':[4,5,0],
'id2':[7,8,2]}).set_index(['id1','id2'])['date']
print (s)
id1 id2
4 7 2015-01-01
5 8 2015-01-02
0 2 2015-01-03
Name: date, dtype: datetime64[ns]
df1 = df.merge(s.to_frame(), on=['id1','id2','date'])
print (df1)
date F
id1 id2
4 7 2015-01-01 a
5 8 2015-01-02 a
另一个解决方案:
df1 = df.reset_index().merge(s.reset_index(), on=['id1','id2','date'])
print (df1)
id1 id2 date F
0 4 7 2015-01-01 a
1 5 8 2015-01-02 a
解决方案
reindex
是可能的,但需要
MultiIndex
锿:
s_index = s.to_frame().assign(tmp=1).set_index('date', append=True).index
idx = df.index.intersection(s_index)
df1 = df.reindex(idx)
print (df1)
F
id1 id2 date
4 7 2015-01-01 a
5 8 2015-01-02 a