1

我有一个熊猫数据框，其中有一列模型变量及其相应的统计信息在另一列中。我已经完成了一些字符串操作以获取派生的汇总表以从模型中加入汇总表。
lost_cost_final_table.loc[lost_cost_final_table['variable'].str.contains('class_cc', case = False), 'variable'] = lost_cost_final_table['variable'].str[:8]

完整的追溯。

---------------------------------------------------------------------------
ValueError                                Traceback (most recent call last)
<ipython-input-229-1dbe5bd14d4b> in <module>
----> 1 lost_cost_final_table.loc[lost_cost_final_table['variable'].str.contains('class_cc', case = False), 'variable'] = lost_cost_final_table['variable'].str[:8]
      2 #lost_cost_final_table.loc[lost_cost_final_table['variable'].str.contains('class_v_age', case = False), 'variable'] = lost_cost_final_table['variable'].str[:11]
      3 #lost_cost_final_table.loc[lost_cost_final_table['variable'].str.contains('married_age', case = False), 'variable'] = lost_cost_final_table['variable'].str[:11]
      4 #lost_cost_final_table.loc[lost_cost_final_table['variable'].str.contains('state_model', case = False), 'variable'] = lost_cost_final_table['variable'].str[:11]
      5 

C:\ProgramData\Anaconda3\lib\site-packages\pandas\core\indexing.py in __setitem__(self, key, value)
    187             key = com._apply_if_callable(key, self.obj)
    188         indexer = self._get_setitem_indexer(key)
--> 189         self._setitem_with_indexer(indexer, value)
    190 
    191     def _validate_key(self, key, axis):

C:\ProgramData\Anaconda3\lib\site-packages\pandas\core\indexing.py in _setitem_with_indexer(self, indexer, value)
    467 
    468             if isinstance(value, ABCSeries):
--> 469                 value = self._align_series(indexer, value)
    470 
    471             info_idx = indexer[info_axis]

C:\ProgramData\Anaconda3\lib\site-packages\pandas\core\indexing.py in _align_series(self, indexer, ser, multiindex_indexer)
    732                         return ser._values.copy()
    733 
--> 734                     return ser.reindex(new_ix)._values
    735 
    736                 # 2 dims

C:\ProgramData\Anaconda3\lib\site-packages\pandas\core\series.py in reindex(self, index, **kwargs)
   3323     @Appender(generic._shared_docs['reindex'] % _shared_doc_kwargs)
   3324     def reindex(self, index=None, **kwargs):
-> 3325         return super(Series, self).reindex(index=index, **kwargs)
   3326 
   3327     def drop(self, labels=None, axis=0, index=None, columns=None,

C:\ProgramData\Anaconda3\lib\site-packages\pandas\core\generic.py in reindex(self, *args, **kwargs)
   3687         # perform the reindex on the axes
   3688         return self._reindex_axes(axes, level, limit, tolerance, method,
-> 3689                                   fill_value, copy).__finalize__(self)
   3690 
   3691     def _reindex_axes(self, axes, level, limit, tolerance, method, fill_value,

C:\ProgramData\Anaconda3\lib\site-packages\pandas\core\generic.py in _reindex_axes(self, axes, level, limit, tolerance, method, fill_value, copy)
   3705             obj = obj._reindex_with_indexers({axis: [new_index, indexer]},
   3706                                              fill_value=fill_value,
-> 3707                                              copy=copy, allow_dups=False)
   3708 
   3709         return obj

C:\ProgramData\Anaconda3\lib\site-packages\pandas\core\generic.py in _reindex_with_indexers(self, reindexers, fill_value, copy, allow_dups)
   3808                                                 fill_value=fill_value,
   3809                                                 allow_dups=allow_dups,
-> 3810                                                 copy=copy)
   3811 
   3812         if copy and new_data is self._data:

C:\ProgramData\Anaconda3\lib\site-packages\pandas\core\internals.py in reindex_indexer(self, new_axis, indexer, axis, fill_value, allow_dups, copy)
   4412         # some axes don't allow reindexing with dups
   4413         if not allow_dups:
-> 4414             self.axes[axis]._can_reindex(indexer)
   4415 
   4416         if axis >= self.ndim:

C:\ProgramData\Anaconda3\lib\site-packages\pandas\core\indexes\base.py in _can_reindex(self, indexer)
   3574         # trying to reindex on an axis with duplicates
   3575         if not self.is_unique and len(indexer):
-> 3576             raise ValueError("cannot reindex from a duplicate axis")
   3577 
   3578     def reindex(self, target, method=None, level=None, limit=None,

ValueError: cannot reindex from a duplicate axis

但是，当我用示例替换时，它可以工作，唯一的区别是数据框名称。见下文。我看不出两个代码行之间的区别在哪里。有任何想法吗？

 variable = ['class_cc-Harley', 'class_cc_Sport', 'class_cc_Other', 'unit_driver_experience']
unique_value = [1200, 1400, 700, 45]
p_value = [.0001, .0001, .0001, .049]
dic = {'variable': variable, 'unique_value':unique_value, 'p_value':p_value}
df = pd.DataFrame(dic)

df.loc[df['variable'].str.contains('class_cc', case = False), 'variable'] = df['variable'].str[:8]
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1 回答 1

1

的索引lost_cost_final_table不是唯一的，可以通过运行来修复reset_index：

lost_cost_final_table.reset_index(inplace=True)
于 2019-05-03T19:15:13.133 回答