我有此代码：
missing_columns = list(set(model_header) - set(combined_data.columns))
if missing_columns:
combined_data = combined_data.reindex(columns=np.append(combined_data.columns.values, missing_columns))
有时会产生此错误
无法从重复的轴重新索引
我从其他帖子中了解到，当您有重复的列时会发生这种情况，但是我不知道如何添加缺少的列
这是回溯
Traceback:
File "/home/henry/Documents/Sites/Development/web-cdi/env/local/lib/python2.7/site-packages/django/core/handlers/exception.py" in inner
41. response = get_response(request)
File "/home/henry/Documents/Sites/Development/web-cdi/env/local/lib/python2.7/site-packages/django/core/handlers/base.py" in _legacy_get_response
249. response = self._get_response(request)
File "/home/henry/Documents/Sites/Development/web-cdi/env/local/lib/python2.7/site-packages/django/core/handlers/base.py" in _get_response
187. response = self.process_exception_by_middleware(e, request)
File "/home/henry/Documents/Sites/Development/web-cdi/env/local/lib/python2.7/site-packages/django/core/handlers/base.py" in _get_response
185. response = wrapped_callback(request, *callback_args, **callback_kwargs)
File "/home/henry/Documents/Sites/Development/web-cdi/env/local/lib/python2.7/site-packages/django/contrib/admin/options.py" in wrapper
552. return self.admin_site.admin_view(view)(*args, **kwargs)
File "/home/henry/Documents/Sites/Development/web-cdi/env/local/lib/python2.7/site-packages/django/utils/decorators.py" in _wrapped_view
149. response = view_func(request, *args, **kwargs)
File "/home/henry/Documents/Sites/Development/web-cdi/env/local/lib/python2.7/site-packages/django/views/decorators/cache.py" in _wrapped_view_func
57. response = view_func(request, *args, **kwargs)
File "/home/henry/Documents/Sites/Development/web-cdi/env/local/lib/python2.7/site-packages/django/contrib/admin/sites.py" in inner
224. return view(request, *args, **kwargs)
File "/home/henry/Documents/Sites/Development/web-cdi/env/local/lib/python2.7/site-packages/django/utils/decorators.py" in _wrapper
67. return bound_func(*args, **kwargs)
File "/home/henry/Documents/Sites/Development/web-cdi/env/local/lib/python2.7/site-packages/django/utils/decorators.py" in _wrapped_view
149. response = view_func(request, *args, **kwargs)
File "/home/henry/Documents/Sites/Development/web-cdi/env/local/lib/python2.7/site-packages/django/utils/decorators.py" in bound_func
63. return func.__get__(self, type(self))(*args2, **kwargs2)
File "/home/henry/Documents/Sites/Development/web-cdi/env/local/lib/python2.7/site-packages/django/contrib/admin/options.py" in changelist_view
1590. response = self.response_action(request, queryset=cl.get_queryset(request))
File "/home/henry/Documents/Sites/Development/web-cdi/env/local/lib/python2.7/site-packages/django/contrib/admin/options.py" in response_action
1287. response = func(self, request, queryset)
File "/home/henry/Documents/Sites/Development/web-cdi/webcdi/researcher_UI/admin_actions.py" in scoring_data
20. return download_data(request, study_obj, administrations)
File "/home/henry/Documents/Sites/Development/web-cdi/env/local/lib/python2.7/site-packages/django/contrib/auth/decorators.py" in _wrapped_view
23. return view_func(request, *args, **kwargs)
File "/home/henry/Documents/Sites/Development/web-cdi/webcdi/researcher_UI/views.py" in download_data
145. combined_data = combined_data.reindex(columns=np.append(combined_data.columns.values, missing_columns))
File "/home/henry/Documents/Sites/Development/web-cdi/env/local/lib/python2.7/site-packages/pandas/core/frame.py" in reindex
2733. **kwargs)
File "/home/henry/Documents/Sites/Development/web-cdi/env/local/lib/python2.7/site-packages/pandas/core/generic.py" in reindex
2515. fill_value, copy).__finalize__(self)
File "/home/henry/Documents/Sites/Development/web-cdi/env/local/lib/python2.7/site-packages/pandas/core/frame.py" in _reindex_axes
2674. fill_value, limit, tolerance)
File "/home/henry/Documents/Sites/Development/web-cdi/env/local/lib/python2.7/site-packages/pandas/core/frame.py" in _reindex_columns
2699. allow_dups=False)
File "/home/henry/Documents/Sites/Development/web-cdi/env/local/lib/python2.7/site-packages/pandas/core/generic.py" in _reindex_with_indexers
2627. copy=copy)
File "/home/henry/Documents/Sites/Development/web-cdi/env/local/lib/python2.7/site-packages/pandas/core/internals.py" in reindex_indexer
3886. self.axes[axis]._can_reindex(indexer)
File "/home/henry/Documents/Sites/Development/web-cdi/env/local/lib/python2.7/site-packages/pandas/core/indexes/base.py" in _can_reindex
2836. raise ValueError("cannot reindex from a duplicate axis")
Exception Type: ValueError at /wcadmin/researcher_UI/study/
Exception Value: cannot reindex from a duplicate axis
我已经查看了各列，但没有看到任何重叠。还可以吗？
答案 0 :(得分：2)
我猜在DataFrames之一或两者中都有重复的列名，解决方案是在解决方案之前手动或通过以下代码对它们进行重复数据删除：
model_header = pd.DataFrame(columns=list('ABDB'))
combined_data = pd.DataFrame(columns=list('ABCA'))
print (model_header)
Empty DataFrame
Columns: [A, B, D, B]
Index: []
print (combined_data)
Empty DataFrame
Columns: [A, B, C, A]
Index: []
s1 = model_header.columns.to_series()
model_header.columns = (model_header.columns +
s1.groupby(s1).cumcount().astype(str).radd('_').str.replace('_0',''))
s2 = combined_data.columns.to_series()
combined_data.columns = (combined_data.columns +
s2.groupby(s2).cumcount().astype(str).radd('_').str.replace('_0',''))
print (model_header)
Empty DataFrame
Columns: [A, B, D, B_1]
Index: []
print (combined_data)
Empty DataFrame
Columns: [A, B, C, A_1]
Index: []
missing_columns = list(set(model_header) - set(combined_data.columns))
print (missing_columns)
['D', 'B_1']
if missing_columns:
combined_data = combined_data.reindex(columns=np.append(combined_data.columns.values, missing_columns))
print (combined_data)
Empty DataFrame
Columns: [A, B, C, A_1, D, B_1]
Index: []