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我的训练数据train SFrame看起来像这样,有 4 列(“Store”列在此 SFrame中不唯一):

+-------+------------+---------+-----------+
| Store |    Date    |  Sales  | Customers |
+-------+------------+---------+-----------+
|   1   | 2015-07-31 |  5263.0 |   555.0   |
|   2   | 2015-07-31 |  6064.0 |   625.0   |
|   3   | 2015-07-31 |  8314.0 |   821.0   |
|   4   | 2015-07-31 | 13995.0 |   1498.0  |
|   3   | 2015-07-20 |  4822.0 |   559.0   |
|   2   | 2015-07-10 |  5651.0 |   589.0   |
|   4   | 2015-07-11 | 15344.0 |   1414.0  |
|   5   | 2015-07-23 |  8492.0 |   833.0   |
|   2   | 2015-07-19 |  8565.0 |   687.0   |
|   10  | 2015-07-09 |  7185.0 |   681.0   |
+-------+------------+---------+-----------+
[986159 rows x 4 columns]

给定第二个store SFrame(“Store”列在此 SFrame 中是唯一的):

+-------+-----------+
| Store | StoreType |
+-------+-----------+
|   1   |     c     |
|   2   |     a     |
|   3   |     a     |
|   4   |     c     |
|   5   |     a     |
|   6   |     a     |
|   7   |     a     |
|   8   |     a     |
|   9   |     a     |
|   10  |     a     |
+-------+-----------+

我可以通过遍历中的每一行并找到适当的 from然后保留列和 ise来将适当的附加StoreType到我的:train SFrametrainStoreTypestoreSFrame.add_column()

store_type_col = []
for row in train:
    row_store = row['Store']
    row_storetype = next(i for i in store if i['Store'] == row_store)['StoreType']
    store_type_col.append(row_storetype)

train.add_column(graphlab.SArray(store_type_col, dtype=str), name='StoreType')

要得到:

+-------+------------+---------+-----------+-----------+
| Store |    Date    |  Sales  | Customers | StoreType |
+-------+------------+---------+-----------+-----------+
|   1   | 2015-07-31 |  5263.0 |   555.0   |   c 
|   2   | 2015-07-31 |  6064.0 |   625.0   |   a 
|   3   | 2015-07-31 |  8314.0 |   821.0   |   a
|   4   | 2015-07-31 | 13995.0 |   1498.0  |   c
|   3   | 2015-07-20 |  4822.0 |   559.0   |   a
|   2   | 2015-07-10 |  5651.0 |   589.0   |   a
|   4   | 2015-07-11 | 15344.0 |   1414.0  |   c
|   5   | 2015-07-23 |  8492.0 |   833.0   |   a
|   2   | 2015-07-19 |  8565.0 |   687.0   |   a
|   10  | 2015-07-09 |  7185.0 |   681.0   |   a
+-------+------------+---------+-----------+-----------+
[986159 rows x 5 columns]

但我确信有一种更简单、更快捷的方法可以使用Graphlab. 当前方法具有O(n*m)n = no的最坏情况。中的行数train,m = 否。中的行数m

想象一下,我store SFrame有 8 列要附加到train. 上面的代码效率非常低。

我还能如何将数据列从一个 SFrame 附加到另一个 SFrame?(也欢迎 Pandas 解决方案)

4

1 回答 1

1

您可以使用操作来执行此join操作。

out = train.join(store, on = 'Store')

于 2015-11-18T08:00:55.137 回答