pandas 使用python重新采样数据帧时出错
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Error when resample dataframe with python
提问by Poisson
I create a dataframe
我创建了一个数据框
df5 = pd.read_csv('C:/Users/Demonstrator/Downloads/Listeequipement.csv',delimiter=';', parse_dates=[0], infer_datetime_format = True)
df5['TIMESTAMP'] = pd.to_datetime(df5['TIMESTAMP'], '%d/%m/%y %H:%M')
df5['date'] = df5['TIMESTAMP'].dt.date
df5['time'] = df5['TIMESTAMP'].dt.time
date_debut = pd.to_datetime('2015-08-01 23:10:00')
date_fin = pd.to_datetime('2015-10-01 00:00:00')
df5 = df5[(df5['TIMESTAMP'] >= date_debut) & (df5['TIMESTAMP'] < date_fin)]
df5.info()
<class 'pandas.core.frame.DataFrame'>
Int64Index: 8645 entries, 145 to 8789
Data columns (total 9 columns):
TIMESTAMP 8645 non-null datetime64[ns]
ACT_TIME_AERATEUR_1_F1 8645 non-null float64
ACT_TIME_AERATEUR_1_F3 8645 non-null float64
ACT_TIME_AERATEUR_1_F5 8645 non-null float64
ACT_TIME_AERATEUR_1_F6 8645 non-null float64
ACT_TIME_AERATEUR_1_F7 8645 non-null float64
ACT_TIME_AERATEUR_1_F8 8645 non-null float64
date 8645 non-null object
time 8645 non-null object
dtypes: datetime64[ns](1), float64(6), object(2)
memory usage: 675.4+ KB
I try to resample it per day like this :
我尝试每天像这样重新采样：
df5.index = pd.to_datetime(df5.index)
df5 = df5.set_index('TIMESTAMP')
df5 = df5.resample('1d').mean()
But I get a problem :
但我遇到了一个问题：
KeyError Traceback (most recent call last) C:\Users\Demonstrator\Anaconda3\lib\site-packages\pandas\indexes\base.pyin 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: 'TIMESTAMP' During handling of the above exception, another exception occurred: KeyError Traceback (most recent call last) <ipython-input-109-bf3238788c3e> in <module>() 1 df5.index = pd.to_datetime(df5.index) ----> 2 df5 = df5.set_index('TIMESTAMP') 3 df5 = df5.resample('1d').mean() C:\Users\Demonstrator\Anaconda3\lib\site-packages\pandas\core\frame.pyin set_index(self, keys, drop, append, inplace, verify_integrity) 2835 names.append(None) 2836 else: -> 2837 level = frame[col]._values 2838 names.append(col) 2839 if drop:
C:\Users\Demonstrator\Anaconda3\lib\site-packages\pandas\core\frame.pyin getitem(self, key) 1995 return self._getitem_multilevel(key) 1996 else: -> 1997 return self._getitem_column(key) 1998 1999 def _getitem_column(self, key):
C:\Users\Demonstrator\Anaconda3\lib\site-packages\pandas\core\frame.pyin _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
C:\Users\Demonstrator\Anaconda3\lib\site-packages\pandas\core\generic.pyin _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
C:\Users\Demonstrator\Anaconda3\lib\site-packages\pandas\core\internals.pyin 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)]
C:\Users\Demonstrator\Anaconda3\lib\site-packages\pandas\indexes\base.pyin 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: 'TIMESTAMP'
KeyError Traceback (most recent call last) C:\Users\Demonstrator\Anaconda3\lib\site-packages\pandas\indexes\base.py在 get_loc(self, key, method, tolerance) 1944 中尝试：-> 1945 return self._engine.get_loc(key) 1946 除了 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: 'TIMESTAMP' During handling of the above exception, another exception occurred: KeyError Traceback (most recent call last) <ipython-input-109-bf3238788c3e> in <module>() 1 df5.index = pd.to_datetime(df5.index) ----> 2 df5 = df5.set_index('TIMESTAMP') 3 df5 = df5.resample('1d').mean() C:\Users\Demonstrator\Anaconda3\lib\site-packages\pandas\core\frame.py在 set_index(self, keys, drop, append, inplace, verify_integrity) 2835 names.append(None) 2836 else: -> 2837 level = frame[col]._values 2838 names.append(col) 2839 if drop：
C:\Users\Demonstrator\Anaconda3\lib\site-packages\pandas\core\frame.py在getitem(self, key) 1995 return self._getitem_multilevel(key) 1996 else: -> 1997 return self._getitem_column(key) 1998 1999 def _getitem_column(self, key):
C:\Users\Demonstrator\Anaconda3\lib\site-packages\pandas\core\frame.pyin _getitem_column(self, key) 2002 # get column 2003 if self.columns.is_unique: -> 2004 return self._get_item_cache(key) 2005 2006 # 重复列和可能的降低维度
C:\Users\Demonstrator\Anaconda3\lib\site-packages\pandas\core\generic.py在 _get_item_cache(self, item) 1348 res = cache.get(item) 1349 如果 res 是 None: -> 1350 values = self._data.get(item) 1351 res = self._box_item_values(item, values) 1352 cache[item ] = 资源
C:\Users\Demonstrator\Anaconda3\lib\site-packages\pandas\core\internals.py在 get(self, item, fastpath) 3288 3289 如果不是 isnull(item): -> 3290 loc = self.items.get_loc(item) 3291 else: 3292 indexer = np.arange(len(self.items))[isnull (self.items)]
C:\Users\Demonstrator\Anaconda3\lib\site-packages\pandas\indexes\base.py在 get_loc(self、key、method、tolerance) 1945 中返回 self._engine.get_loc(key) 1946 除了 KeyError：-> 1947 返回 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: 'TIMESTAMP'
Any idea please to help me to resolve this problem?
任何想法请帮助我解决这个问题？
Kind regards
亲切的问候
回答by SerialDev
remove pd.to_datetimeand try df.set_indexdirectly:
删除pd.to_datetime并df.set_index直接尝试：
*df5.index = pd.to_datetime(df5.index)* # Delete this one
df5 = df5.set_index('TIMESTAMP')
df5 = df5.resample('1d').mean()
