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Я искренне не разбираюсь в этом вопросе. Я пытался создать пару столбцов из фрейма данных, но я получаю ValueError: Wrong number of items passed 2, placement implies 1 . Каким-то образом я могу создать его, не имеет значения, является ли это window = 7 или window = 14, но разрешено создавать только один. Вот мой код:

 import pandas as pd
from datetime import datetime, timedelta

suspects_url = 'https://raw.githubusercontent.com/mariorz/covid19-mx-time-series/master/data/covid19_suspects_mx.csv'
suspects = pd.read_csv(suspects_url, index_col=0)
suspects = suspects.loc['Colima']
suspects = pd.DataFrame(suspects)
suspects.index = pd.to_datetime(suspects.index, format='%d-%m-%Y')
suspects['suspects_ma_7'] = suspects.rolling(window=7).mean()
suspects['suspects_ma_14'] = suspects.rolling(window=14).mean()
suspects.columns = ['suspects','suspects_ma_7','suspects_ma_14']

suspects
 

И это ошибка, которую я получаю:

 KeyError                                  Traceback (most recent call last)
/Library/Frameworks/Python.framework/Versions/3.8/lib/python3.8/site-packages/pandas/core/indexes/base.py in get_loc(self, key, method, tolerance)
   2645             try:
-> 2646                 return self._engine.get_loc(key)
   2647             except KeyError:

pandas/_libs/index.pyx in pandas._libs.index.IndexEngine.get_loc()

pandas/_libs/index.pyx in pandas._libs.index.IndexEngine.get_loc()

pandas/_libs/hashtable_class_helper.pxi in pandas._libs.hashtable.PyObjectHashTable.get_item()

pandas/_libs/hashtable_class_helper.pxi in pandas._libs.hashtable.PyObjectHashTable.get_item()

KeyError: 'suspects_ma_14'

During handling of the above exception, another exception occurred:

KeyError                                  Traceback (most recent call last)
/Library/Frameworks/Python.framework/Versions/3.8/lib/python3.8/site-packages/pandas/core/internals/managers.py in set(self, item, value)
   1070         try:
-> 1071             loc = self.items.get_loc(item)
   1072         except KeyError:

/Library/Frameworks/Python.framework/Versions/3.8/lib/python3.8/site-packages/pandas/core/indexes/base.py in get_loc(self, key, method, tolerance)
   2647             except KeyError:
-> 2648                 return self._engine.get_loc(self._maybe_cast_indexer(key))
   2649         indexer = self.get_indexer([key], method=method, tolerance=tolerance)

pandas/_libs/index.pyx in pandas._libs.index.IndexEngine.get_loc()

pandas/_libs/index.pyx in pandas._libs.index.IndexEngine.get_loc()

pandas/_libs/hashtable_class_helper.pxi in pandas._libs.hashtable.PyObjectHashTable.get_item()

pandas/_libs/hashtable_class_helper.pxi in pandas._libs.hashtable.PyObjectHashTable.get_item()

KeyError: 'suspects_ma_14'

During handling of the above exception, another exception occurred:

ValueError                                Traceback (most recent call last)
<ipython-input-6-4138f1be9342> in <module>
      5 suspects.index = pd.to_datetime(suspects.index, format='%d-%m-%Y')
      6 suspects['suspects_ma_7'] = suspects.rolling(window=7).mean()
----> 7 suspects['suspects_ma_14'] = suspects.rolling(window=14).mean()
      8 suspects.columns = ['suspects','suspects_ma_7','suspects_ma_14']
      9 

/Library/Frameworks/Python.framework/Versions/3.8/lib/python3.8/site-packages/pandas/core/frame.py in __setitem__(self, key, value)
   2936         else:
   2937             # set column
-> 2938             self._set_item(key, value)
   2939 
   2940     def _setitem_slice(self, key, value):

/Library/Frameworks/Python.framework/Versions/3.8/lib/python3.8/site-packages/pandas/core/frame.py in _set_item(self, key, value)
   2999         self._ensure_valid_index(value)
   3000         value = self._sanitize_column(key, value)
-> 3001         NDFrame._set_item(self, key, value)
   3002 
   3003         # check if we are modifying a copy

/Library/Frameworks/Python.framework/Versions/3.8/lib/python3.8/site-packages/pandas/core/generic.py in _set_item(self, key, value)
   3622 
   3623     def _set_item(self, key, value) -> None:
-> 3624         self._data.set(key, value)
   3625         self._clear_item_cache()
   3626 

/Library/Frameworks/Python.framework/Versions/3.8/lib/python3.8/site-packages/pandas/core/internals/managers.py in set(self, item, value)
   1072         except KeyError:
   1073             # This item wasn't present, just insert at end
-> 1074             self.insert(len(self.items), item, value)
   1075             return
   1076 

/Library/Frameworks/Python.framework/Versions/3.8/lib/python3.8/site-packages/pandas/core/internals/managers.py in insert(self, loc, item, value, allow_duplicates)
   1179         new_axis = self.items.insert(loc, item)
   1180 
-> 1181         block = make_block(values=value, ndim=self.ndim, placement=slice(loc, loc   1))
   1182 
   1183         for blkno, count in _fast_count_smallints(self._blknos[loc:]):

/Library/Frameworks/Python.framework/Versions/3.8/lib/python3.8/site-packages/pandas/core/internals/blocks.py in make_block(values, placement, klass, ndim, dtype)
   3045         values = DatetimeArray._simple_new(values, dtype=dtype)
   3046 
-> 3047     return klass(values, ndim=ndim, placement=placement)
   3048 
   3049 

/Library/Frameworks/Python.framework/Versions/3.8/lib/python3.8/site-packages/pandas/core/internals/blocks.py in __init__(self, values, placement, ndim)
    122 
    123         if self._validate_ndim and self.ndim and len(self.mgr_locs) != len(self.values):
--> 124             raise ValueError(
    125                 f"Wrong number of items passed {len(self.values)}, "
    126                 f"placement implies {len(self.mgr_locs)}"

ValueError: Wrong number of items passed 2, placement implies 1
 

Как я могу решить эту проблему?

Я настаиваю, что при моих попытках только с одним suspects_ma_# это работает. Но когда я пытаюсь создать и то, и другое, я просто получаю сообщение об ошибке.

При первом запуске suspects['suspects_ma_7'] = suspects.rolling(window=7).mean() вы автоматически преобразуете свой ряд в фрейм данных.

Итак, для выполнения второго rolling подхода используйте:

 suspects['suspects_ma_7'] = suspects.Colima.rolling(window=7).mean()
 

Обратите внимание на « suspects.Colima » в приведенном выше коде.