Pandas 中的周期性 KeyError

Question

我想使用已经存在的随机值替换数据框中的空值，同时保持权重，这样相关性就不会受到影响，数据也不会丢失。

def nan_fill_random(column_name, nan):
for i in range(len(column_name)):
    if column_name[i] == nan:
        column_name[i] = random.choice(column_name[column_name != nan])
    else:
        continue

我写了一个函数，但它周期性地抛出一个KeyError：并且值有不同的数字，我假设索引。此外，当您重新启动单元时，它可能会消失或更新。

nan_fill_random(data['education'], 'unknown')

这里是错误

    ---------------------------------------------------------------------------
KeyError                                  Traceback (most recent call last)
W:\ProgramData\Anaconda3\lib\site-packages\pandas\core\indexes\base.py in get_loc(self, key, method, tolerance)
   3360             try:
-> 3361                 return self._engine.get_loc(casted_key)
   3362             except KeyError as err:

W:\ProgramData\Anaconda3\lib\site-packages\pandas\_libs\index.pyx in pandas._libs.index.IndexEngine.get_loc()

W:\ProgramData\Anaconda3\lib\site-packages\pandas\_libs\index.pyx in pandas._libs.index.IndexEngine.get_loc()

pandas\_libs\hashtable_class_helper.pxi in pandas._libs.hashtable.Int64HashTable.get_item()

pandas\_libs\hashtable_class_helper.pxi in pandas._libs.hashtable.Int64HashTable.get_item()

KeyError: 14563

The above exception was the direct cause of the following exception:

KeyError                                  Traceback (most recent call last)
~\AppData\Local\Temp/ipykernel_4720/2723938638.py in <module>
----> 1 nan_fill_random(data['education'], 'unknown')

~\AppData\Local\Temp/ipykernel_4720/1980306790.py in nan_fill_random(column_name, nan)
      2     for i in range(len(column_name)):
      3         if column_name[i] == nan:
----> 4             column_name[i] = random.choice(column_name[column_name != nan])
      5         else:
      6             continue

W:\ProgramData\Anaconda3\lib\random.py in choice(self, seq)
    344         """Choose a random element from a non-empty sequence."""
    345         # raises IndexError if seq is empty
--> 346         return seq[self._randbelow(len(seq))]
    347 
    348     def shuffle(self, x, random=None):

W:\ProgramData\Anaconda3\lib\site-packages\pandas\core\series.py in __getitem__(self, key)
    940 
    941         elif key_is_scalar:
--> 942             return self._get_value(key)
    943 
    944         if is_hashable(key):

W:\ProgramData\Anaconda3\lib\site-packages\pandas\core\series.py in _get_value(self, label, takeable)
   1049 
   1050         # Similar to Index.get_value, but we do not fall back to positional
-> 1051         loc = self.index.get_loc(label)
   1052         return self.index._get_values_for_loc(self, loc, label)
   1053 

W:\ProgramData\Anaconda3\lib\site-packages\pandas\core\indexes\base.py in get_loc(self, key, method, tolerance)
   3361                 return self._engine.get_loc(casted_key)
   3362             except KeyError as err:
-> 3363                 raise KeyError(key) from err
   3364 
   3365         if is_scalar(key) and isna(key) and not self.hasnans:

KeyError: 14563

Answer 1

def nan_fill_random(column_name, nan):
    
    list_values = set(column_name)
    
    try : 
        list_values.remove(nan)
    except : 
        return(column_name)
    
    column_name = column_name.apply(lambda x: x if x != nan else random.choice(list(list_values)))
        
    return(column_name)

Pandas 中的周期性 KeyError

Periodic KeyError in Pandas

python

random

pandas