Question

当尝试计算熊猫数据框中的某些概率时，我得到KeyError：“ ENABLEchain”，当我在此站点上查找时，结果为零。

这种情况是，我加载了多个.csv文件，并计算了文件中行的概率。 .cvs文件如下所示：

"sequence","support"
"<{10052Regainstart},{10053Regainready}>",0.994708994708995
"<{10125Programstopped},{10052Regainstart},{10053Regainready}>",0.994708994708995
"<{10125Programstopped},{10052Regainstart}>",0.994708994708995

我的代码如下：

# import the files in a glob set of files, ordered!
files = sorted(glob.glob("/Users/.../threshold_value_*.csv"))

# loop over all the files in glob, calculate the probabilities
for f in files:
    rules = pd.read_csv(f, usecols=[0,1]) 
    rules['sequence'] = rules['sequence'].str.replace('{|}|<|>','') #only keep the comma's
    rules.insert(1, 'length', rules['sequence'].str.count(',') + 1) # count number of events in the pattern
    probability = rules['sequence'].str.split(',').apply(lambda x: get_prob(*x)) #calculate markov chain prob

rules

函数get_prob如下：

def get_prob(*args):
    ret = 1
    for i, j in zip(args, args[1:]):
        ret *= probs.at[i,j]
    return ret

计算模式.csv文件中行的概率。概率数据帧看起来像这样，因此使用* args和.at [i，j]我们可以计算出模式.csv文件中所有行的概率：

           event23     event24     event34
event23    0.34        0.88        0.54
event24    0.87        0.45        0.33
event34    0.98        0.23        0.34

错误代码如下：

KeyError                                  Traceback (most recent call last)
~/anaconda3/lib/python3.7/site-packages/pandas/core/indexes/base.py in get_loc(self, key, method, tolerance)
   2656             try:
-> 2657                 return self._engine.get_loc(key)
   2658             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: 'ENABLEchain'

During handling of the above exception, another exception occurred:

KeyError                                  Traceback (most recent call last)
<ipython-input-59-c914483e45d6> in <module>
     12     rules['sequence'] = rules['sequence'].str.replace('{|}|<|>','') #replace some characters
     13     rules.insert(1, 'length', rules['sequence'].str.count(',') + 1) # count number of events in the pattern
---> 14     probability = rules['sequence'].str.split(',').apply(lambda x: get_prob(*x)) #calculate markov chain prob
     15 
     16 rules

~/anaconda3/lib/python3.7/site-packages/pandas/core/series.py in apply(self, func, convert_dtype, args, **kwds)
   3589             else:
   3590                 values = self.astype(object).values
-> 3591                 mapped = lib.map_infer(values, f, convert=convert_dtype)
   3592 
   3593         if len(mapped) and isinstance(mapped[0], Series):

pandas/_libs/lib.pyx in pandas._libs.lib.map_infer()

<ipython-input-59-c914483e45d6> in <lambda>(x)
     12     rules['sequence'] = rules['sequence'].str.replace('{|}|<|>','') #replace some characters
     13     rules.insert(1, 'length', rules['sequence'].str.count(',') + 1) # count number of events in the pattern
---> 14     probability = rules['sequence'].str.split(',').apply(lambda x: get_prob(*x)) #calculate markov chain prob
     15 
     16 rules

<ipython-input-57-94f2040b6b35> in get_prob(*args)
      2     ret = 1
      3     for i, j in zip(args, args[1:]):
----> 4         ret *= probs.at[i,j]
      5 
      6     return ret

~/anaconda3/lib/python3.7/site-packages/pandas/core/indexing.py in __getitem__(self, key)
   2268 
   2269         key = self._convert_key(key)
-> 2270         return self.obj._get_value(*key, takeable=self._takeable)
   2271 
   2272     def __setitem__(self, key, value):

~/anaconda3/lib/python3.7/site-packages/pandas/core/frame.py in _get_value(self, index, col, takeable)
   2765             return com.maybe_box_datetimelike(series._values[index])
   2766 
-> 2767         series = self._get_item_cache(col)
   2768         engine = self.index._engine
   2769 

~/anaconda3/lib/python3.7/site-packages/pandas/core/generic.py in _get_item_cache(self, item)
   3059         res = cache.get(item)
   3060         if res is None:
-> 3061             values = self._data.get(item)
   3062             res = self._box_item_values(item, values)
   3063             cache[item] = res

~/anaconda3/lib/python3.7/site-packages/pandas/core/internals/managers.py in get(self, item, fastpath)
    939 
    940             if not isna(item):
--> 941                 loc = self.items.get_loc(item)
    942             else:
    943                 indexer = np.arange(len(self.items))[isna(self.items)]

~/anaconda3/lib/python3.7/site-packages/pandas/core/indexes/base.py in get_loc(self, key, method, tolerance)
   2657                 return self._engine.get_loc(key)
   2658             except KeyError:
-> 2659                 return self._engine.get_loc(self._maybe_cast_indexer(key))
   2660         indexer = self.get_indexer([key], method=method, tolerance=tolerance)
   2661         if indexer.ndim > 1 or indexer.size > 1:

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: 'ENABLEchain'

我之前从未遇到过此错误，并且google / stackoverflow给我0个结果，有人知道更多吗？

谢谢！

KeyError：“ ENABLEchain”在python-pandas中是什么意思？

0 个答案: