Python reshape DataFrame 列

发布于06月17日

我需要用以下形状reshape 数据帧:

sample_df
Out[97]: 
                    0       1                   2       3
0  2011-01-01 00:00:00  123.39  2012-01-01 00:00:00   123.4
1  2011-01-01 01:00:00  123.39  2012-01-01 01:00:00  123.38
2  2011-01-01 02:00:00   123.4  2012-01-01 02:00:00   123.4
3  2011-01-01 03:00:00   123.4  2012-01-01 03:00:00   123.4
4  2011-01-01 04:00:00  123.41  2012-01-01 04:00:00   123.4

形状如下:

reshaped_sample_df          
Out[97]:            
                      0       1
0   2011-01-01 00:00:00  123.39
1   2011-01-01 01:00:00  123.39
2   2011-01-01 02:00:00   123.4
3   2011-01-01 03:00:00   123.4
4   2011-01-01 04:00:00  123.41
5   2012-01-01 00:00:00   123.4
6   2012-01-01 01:00:00  123.38
7   2012-01-01 02:00:00   123.4
8   2012-01-01 03:00:00   123.4
9   2012-01-01 04:00:00   123.4

我一直在努力reshape Pandas 的数据功能，但并没有成功.

推荐答案

对于一般方式，可以在循环中使用pandas.concat:

out = pd.concat([df.iloc[:, x:x+2].set_axis([0, 1], axis=1)
                 for x in range(0, df.shape[1], 2)],
                ignore_index=True)

输出:

                     0       1
0  2011-01-01 00:00:00  123.39
1  2011-01-01 01:00:00  123.39
2  2011-01-01 02:00:00  123.40
3  2011-01-01 03:00:00  123.40
4  2011-01-01 04:00:00  123.41
5  2012-01-01 00:00:00  123.40
6  2012-01-01 01:00:00  123.38
7  2012-01-01 02:00:00  123.40
8  2012-01-01 03:00:00  123.40
9  2012-01-01 04:00:00  123.40