如何复制/复制熊猫数据框行答案

【问题标题】：How to replicate/ copy pandas dataframe rows如何复制/复制熊猫数据框行
【发布时间】：2021-09-06 17:32:25
【问题描述】：

我需要将相同的行块复制到该块下方 3 次。如下例所示。

数据帧（df1）：-

S.No    Cal        Date              DFM

  1            8       01-03-2013   100.00%
  1            7       01-06-2013   100.00%
  1            6       01-09-2013   100.00%
  1            5       01-12-2013   99.99%
  1            4       01-03-2014   99.97%
  1            3       01-06-2014   99.95%
  1            2       01-09-2014   98.89%
  1            1      01-12-2014   39.36%
  1            0      01-03-2015   0.00%
  1            0      01-06-2015   0.00%
  1            0      01-09-2015   0.00%
  1            0      01-12-2015   0.00%
  2            8      01-03-2013   100.00%
  2            7      01-06-2013   100.00%
  2            6      01-09-2013   100.00%
  2            5      01-12-2013   99.99%
  2            4      01-03-2014   99.97%
  2            3      01-06-2014   97.95%
  2            2      01-09-2014   94.42%
  2            1      01-12-2014   43.13%
  2            0      01-03-2015   0.00%
  2            0      01-06-2015   0.00%
  2            0      01-09-2015   0.00%
  2            0      01-12-2015   0.00%
  3            8      01-03-2013   100.00%
  3            7      01-06-2013   100.00%
  3            6      01-09-2013   100.00%
  3            5      01-12-2013   99.99%
  3            4      01-03-2014   99.96%
  3            3      01-06-2014   99.94%
  3            2      01-09-2014   98.85%
  3            1      01-12-2014   54.77%
  3            0      01-03-2015   0.00%
  3            0      01-06-2015   0.00%
  3            0      01-09-2015   0.00%
  3            0      01-12-2015   0.00%

结果：-

第一个数据帧：-

S.No     Cal     Date              DFM

  1            8       01-03-2013   100.00%
  1            7       01-06-2013   100.00%
  1            6       01-09-2013   100.00%
  1            5       01-12-2013   99.99%
  1            4       01-03-2014   99.97%
  1            3       01-06-2014   99.95%
  1            2       01-09-2014   98.89%
  1            1      01-12-2014   39.36%
  1            0      01-03-2015   0.00%
  1            0      01-06-2015   0.00%
  1            0      01-09-2015   0.00%
  1            0      01-12-2015   0.00%
  1            8      01-03-2013   100.00%
  1            7      01-06-2013   100.00%
  1            6      01-09-2013   100.00%
  1            5      01-12-2013   99.99%
  1            4      01-03-2014   99.97%
  1            3      01-06-2014   99.95%
  1            2      01-09-2014   98.89%
  1            1      01-12-2014   39.36%
  1            0      01-03-2015   0.00%
  1            0      01-06-2015   0.00%
  1            0      01-09-2015   0.00%
  1            0      01-12-2015   0.00%
  1            8      01-03-2013   100.00%
  1            7      01-06-2013   100.00%
  1            6      01-09-2013   100.00%
  1            5      01-12-2013   99.99%
  1            4      01-03-2014   99.97%
  1            3      01-06-2014   99.95%
  1            2      01-09-2014   98.89%
  1            1      01-12-2014   39.36%
  1            0      01-03-2015   0.00%
  1            0      01-06-2015   0.00%
  1            0      01-09-2015   0.00%
  1            0      01-12-2015   0.00%
  2            8      01-03-2013   100.00%
  2            7      01-06-2013   100.00%
  2            6      01-09-2013   100.00%
  2            5      01-12-2013   99.99%
  2            4      01-03-2014   99.97%
  2            3      01-06-2014   97.95%
  2            2      01-09-2014   94.42%
  2            1      01-12-2014   43.13%
  2            0      01-03-2015   0.00%
  2            0      01-06-2015   0.00%
  2            0      01-09-2015   0.00%
  2            0      01-12-2015   0.00%
  2            8      01-03-2013   100.00%
  2            7      01-06-2013   100.00%
  2            6      01-09-2013   100.00%
  2            5      01-12-2013   99.99%
  2            4      01-03-2014   99.97%
  2            3      01-06-2014   97.95%
  2            2      01-09-2014   94.42%
  2            1      01-12-2014   43.13%
  2            0      01-03-2015   0.00%
  2            0      01-06-2015   0.00%
  2            0      01-09-2015   0.00%
  2            0      01-12-2015   0.00%
  2            8      01-03-2013   100.00%
  2            7      01-06-2013   100.00%
  2            6      01-09-2013   100.00%
  2            5      01-12-2013   99.99%
  2            4      01-03-2014   99.97%
  2            3      01-06-2014   97.95%
  2            2      01-09-2014   94.42%
  2            1      01-12-2014   43.13%
  2            0      01-03-2015   0.00%
  2            0      01-06-2015   0.00%
  2            0      01-09-2015   0.00%
  2            0      01-12-2015   0.00%
  3            8      01-03-2013   100.00%
  3            7      01-06-2013   100.00%
  3            6      01-09-2013   100.00%
  3            5      01-12-2013   99.99%
  3            4      01-03-2014   99.96%
  3            3      01-06-2014   99.94%
  3            2      01-09-2014   98.85%
  3            1      01-12-2014   54.77%
  3            0      01-03-2015   0.00%
  3            0      01-06-2015   0.00%
  3            0      01-09-2015   0.00%
  3            0      01-12-2015   0.00%
  3            8      01-03-2013   100.00%
  3            7      01-06-2013   100.00%
  3            6      01-09-2013   100.00%
  3            5      01-12-2013   99.99%
  3            4      01-03-2014   99.96%
  3            3      01-06-2014   99.94%
  3            2      01-09-2014   98.85%
  3            1      01-12-2014   54.77%
  3            0      01-03-2015   0.00%
  3            0      01-06-2015   0.00%
  3            0      01-09-2015   0.00%
  3            0      01-12-2015   0.00%
  3            8      01-03-2013   100.00%
  3            7      01-06-2013   100.00%
  3            6      01-09-2013   100.00%
  3            5      01-12-2013   99.99%
  3            4      01-03-2014   99.96%
  3            3      01-06-2014   99.94%
  3            2      01-09-2014   98.85%
  3            1      01-12-2014   54.77%
  3            0      01-03-2015   0.00%
  3            0      01-06-2015   0.00%
  3            0      01-09-2015   0.00%
  3            0      01-12-2015   0.00%

【问题讨论】：

标签： python pandas copy replicate

【解决方案1】：

一种方法是按"S.No" 分组，然后返回一个连接的帧并在最后重置索引：

new_df = df.groupby("S.No").apply(lambda d: pd.concat([d]*3)).reset_index(drop=True)

得到

>>> new_df

     S.No  Cal        Date      DFM
0       1    8  01-03-2013  100.00%
1       1    7  01-06-2013  100.00%
2       1    6  01-09-2013  100.00%
3       1    5  01-12-2013   99.99%
4       1    4  01-03-2014   99.97%
..    ...  ...         ...      ...
103     3    1  01-12-2014   54.77%
104     3    0  01-03-2015    0.00%
105     3    0  01-06-2015    0.00%
106     3    0  01-09-2015    0.00%
107     3    0  01-12-2015    0.00%

[108 rows x 4 columns]

【讨论】：

嗨 Mustafa，我需要解决这个问题stackoverflow.com/q/68115846/16292010