我有两个数据框,如下所示:
>>> df1
A B
2000-01-01 1.4 1.4
2000-01-02 1.7 -1.9
2000-01-03 -0.2 -0.8
>>> df2
A B
2000-01-01 0.6 -0.3
2000-01-02 -0.4 0.6
2000-01-03 1.1 -1.0
如何使用下面的分层列索引从这两个中创建一个数据帧?
df1 df2
A B A B
2000-01-01 1.4 1.4 0.6 -0.3
2000-01-02 1.7 -1.9 -0.4 0.6
2000-01-03 -0.2 -0.8 1.1 -1.0
答案 0 :(得分:18)
这是一个文档示例:http://pandas.pydata.org/pandas-docs/stable/merging.html#more-concatenating-with-group-keys
In [9]: df1 = pd.DataFrame(np.random.randn(3,2),columns=list('AB'),index=pd.date_range('20000101',periods=3))
In [10]: df2 = pd.DataFrame(np.random.randn(3,2),columns=list('AB'),index=pd.date_range('20000101',periods=3))
In [11]: df1
Out[11]:
A B
2000-01-01 0.129994 1.189608
2000-01-02 -1.126812 1.087617
2000-01-03 -0.930070 0.253098
In [12]: df2
Out[12]:
A B
2000-01-01 0.535700 -0.769533
2000-01-02 -1.698531 -0.456667
2000-01-03 0.451622 -1.500175
In [13]: pd.concat(dict(df1 = df1, df2 = df2),axis=1)
Out[13]:
df1 df2
A B A B
2000-01-01 0.129994 1.189608 0.535700 -0.769533
2000-01-02 -1.126812 1.087617 -1.698531 -0.456667
2000-01-03 -0.930070 0.253098 0.451622 -1.500175