turicreate.SFrame.unstack¶

SFrame.unstack(column_names, new_column_name=None)¶

Concatenate values from one or two columns into one column, grouping by all other columns. The resulting column could be of type list, array or dictionary. If column_names is a numeric column, the result will be of array.array type. If column_names is a non-numeric column, the new column will be of list type. If column_names is a list of two columns, the new column will be of dict type where the keys are taken from the first column in the list.

Parameters:	column_names : str \| [str, str] The column(s) that is(are) to be concatenated. If str, then collapsed column type is either array or list. If [str, str], then collapsed column type is dict new_column_name : str, optional New column name. If not given, a name is generated automatically.
Returns:	out : SFrame A new SFrame containing the grouped columns as well as the new column.

See also

stack: The inverse of unstack.
groupby: unstack is a special version of groupby that uses the CONCAT aggregator

Notes

There is no guarantee the resulting SFrame maintains the same order as the original SFrame.
Missing values are maintained during unstack.
When unstacking into a dictionary, if there is more than one instance of a given key for a particular group, an arbitrary value is selected.

Examples

>>> sf = turicreate.SFrame({'count':[4, 2, 1, 1, 2, None],
...                       'topic':['cat', 'cat', 'dog', 'elephant', 'elephant', 'fish'],
...                       'word':['a', 'c', 'c', 'a', 'b', None]})
>>> sf.unstack(column_names=['word', 'count'], new_column_name='words')
+----------+------------------+
|  topic   |      words       |
+----------+------------------+
| elephant | {'a': 1, 'b': 2} |
|   dog    |     {'c': 1}     |
|   cat    | {'a': 4, 'c': 2} |
|   fish   |       None       |
+----------+------------------+
[4 rows x 2 columns]

>>> sf = turicreate.SFrame({'friend': [2, 3, 4, 5, 6, 4, 5, 2, 3],
...                      'user': [1, 1, 1, 2, 2, 2, 3, 4, 4]})
>>> sf.unstack('friend', new_column_name='new name')
+------+-----------+
| user |  new name |
+------+-----------+
|  3   |    [5]    |
|  1   | [2, 3, 4] |
|  2   | [6, 4, 5] |
|  4   |   [2, 3]  |
+------+-----------+
[4 rows x 2 columns]