のPython：Chpの2 Pgの38 "prop_cumsum" エラー

Question

私はこの本に取り組んで、私が "Prop_cumsum"

> prop_cumsum = df.sort_index（で=」を実行していたときにエラーを実行し続けています

/Users/anaconda/lib/python3.5/site-packages/ipykernel/main.py:1: FutureWarning: by argument to sort_index is deprecated, pls use .sort_values(by=...) if name == 'main': --------------------------------------------------------------------------- KeyError Traceback (most recent call last) /Users/anaconda/lib/python3.5/site-packages/pandas/indexes/base.py in get_loc(self, key, method, tolerance) 1944 try: -> 1945 return self._engine.get_loc(key) 1946 except KeyError:

pandas/index.pyx in pandas.index.IndexEngine.get_loc (pandas/index.c:4154)()

pandas/index.pyx in pandas.index.IndexEngine.get_loc (pandas/index.c:4018)()

pandas/hashtable.pyx in pandas.hashtable.PyObjectHashTable.get_item (pandas/hashtable.c:12368)()

pandas/hashtable.pyx in pandas.hashtable.PyObjectHashTable.get_item (pandas/hashtable.c:12322)()

KeyError: 'prop'

During handling of the above exception, another exception occurred:

KeyError Traceback (most recent call last) in() ----> 1 prop_cumsum = df.sort_index(by='prop', ascending=False).prop.cumsum()

/Users/anaconda/lib/python3.5/site-packages/pandas/core/frame.py in sort_index(self, axis, level, ascending, inplace, kind, na_position, sort_remaining, by) 3237 raise ValueError("unable to simultaneously sort by and level") 3238 return self.sort_values(by, axis=axis, ascending=ascending, -> 3239 inplace=inplace) 3240 3241 axis = self._get_axis_number(axis)

/Users/anaconda/lib/python3.5/site-packages/pandas/core/frame.py in sort_values(self, by, axis, ascending, inplace, kind, na_position)
3149 3150 by = by[0] -> 3151 k = self[by].values 3152 if k.ndim == 2: 3153

/Users/anaconda/lib/python3.5/site-packages/pandas/core/frame.py in getitem(self, key) 1995 return self._getitem_multilevel(key) 1996 else: -> 1997 return self._getitem_column(key) 1998 1999 def _getitem_column(self, key):

/Users/anaconda/lib/python3.5/site-packages/pandas/core/frame.py in _getitem_column(self, key) 2002 # get column 2003 if self.columns.is_unique: -> 2004 return self._get_item_cache(key) 2005 2006 # duplicate columns & possible reduce dimensionality

/Users/anaconda/lib/python3.5/site-packages/pandas/core/generic.py in _get_item_cache(self, item) 1348 res = cache.get(item) 1349 if res is None: -> 1350 values = self._data.get(item) 1351 res = self._box_item_values(item, values) 1352
cache[item] = res

/Users/anaconda/lib/python3.5/site-packages/pandas/core/internals.py in get(self, item, fastpath) 3288 3289 if not isnull(item): -> 3290 loc = self.items.get_loc(item) 3291 else: 3292 indexer = np.arange(len(self.items))[isnull(self.items)]

/Users/anaconda/lib/python3.5/site-packages/pandas/indexes/base.py in get_loc(self, key, method, tolerance) 1945 return self._engine.get_loc(key) 1946 except KeyError: -> 1947 return self._engine.get_loc(self._maybe_cast_indexer(key)) 1948 1949
indexer = self.get_indexer([key], method=method, tolerance=tolerance)

pandas/index.pyx in pandas.index.IndexEngine.get_loc (pandas/index.c:4154)()

pandas/index.pyx in pandas.index.IndexEngine.get_loc (pandas/index.c:4018)()

pandas/hashtable.pyx in pandas.hashtable.PyObjectHashTable.get_item (pandas/hashtable.c:12368)()

pandas/hashtable.pyx in pandas.hashtable.PyObjectHashTable.get_item (pandas/hashtable.c:12322)()

KeyError: 'prop'

Answer 1

）（「昇順= False）が.prop.cumsumを支えるあなたがsort_index代わりのsort_valuesを呼び出しているようです。 by='prop'は、そのようなコンテキストでは意味をなさない（データフレームの列ではなく、インデックスによってインデックスをソートする）。

また、第2版の初期リリースのコピーでは、43ページの上部付近に表示されます。しかし、これは早期リリースであるため、ページ番号が流動的である可能性があります。