python - Pandas 根据天数列复制 df 行

Question

我有以下 DF。

DF数量

| hold_date  | day_count | qty  |   item   | ccy |
+------------+-----------+------+----------+-----+
| 2015-01-01 |         1 | 1200 | CB04 box | USD |
| 2015-01-01 |         3 | 1500 | AB01 box | USD |
| 2015-01-02 |         2 |  550 | CB03 box | USD |

我想根据 day_count 递增 hold_date。例如 item : AB01 box 将添加如下两行。所以 df 可能看起来像这样。

DF数量

| hold_date  | qty  |   item   | ccy |
+------------+------+----------+-----+
| 2015-01-01 | 1200 | CB04 box | USD |
| 2015-01-01 | 1500 | AB01 box | USD |
| 2015-01-02 | 1500 | AB01 box | USD |
| 2015-01-03 | 1500 | AB01 box | USD |
| 2015-01-02 |  550 | CB03 box | USD |
| 2015-01-03 |  550 | CB03 box | USD |

Answer 1

需要:

s=df.day_count
s1=[pd.Timedelta(x,'D') for x in sum(df.day_count.apply(lambda x : list(range(x))),[])]
df_new=df.reindex(df.index.repeat(s))
df_new['hold_date']=df_new.hold_date+s1
df_new
Out[642]: 
   hold_date  day_count   qty     item  ccy
0 2015-01-01          1  1200  CB04box  USD
1 2015-01-01          3  1500  AB01box  USD
1 2015-01-02          3  1500  AB01box  USD
1 2015-01-03          3  1500  AB01box  USD
2 2015-01-02          2   550  CB03box  USD
2 2015-01-03          2   550  CB03box  USD