Python 破折号回溯未导致代码中的任何行

Python 破折号回溯未导致代码中的任何行,python,pandas,plotly-dash,Python,Pandas,Plotly Dash,我正在开发我的第一款Dash应用程序。我得到以下错误: "Cannot set a frame with no defined index " 问题是回溯不会导致代码中出现任何行。它只通过已安装的库: Traceback (most recent call last): File "C:\Users\LIAG8802\Documents\Procurement_analytics\venv\lib\site-packages\pandas\core\frame.py", line 3540

我正在开发我的第一款Dash应用程序。我得到以下错误:

"Cannot set a frame with no defined index "
问题是回溯不会导致代码中出现任何行。它只通过已安装的库:

Traceback (most recent call last):
  File "C:\Users\LIAG8802\Documents\Procurement_analytics\venv\lib\site-packages\pandas\core\frame.py", line 3540, in _ensure_valid_index
    value = Series(value)
  File "C:\Users\LIAG8802\Documents\Procurement_analytics\venv\lib\site-packages\pandas\core\series.py", line 316, in __init__
    data = SingleBlockManager(data, index, fastpath=True)
  File "C:\Users\LIAG8802\Documents\Procurement_analytics\venv\lib\site-packages\pandas\core\internals\managers.py", line 1516, in __init__
    block = make_block(block, placement=slice(0, len(axis)), ndim=1)
  File "C:\Users\LIAG8802\Documents\Procurement_analytics\venv\lib\site-packages\pandas\core\internals\blocks.py", line 3284, in make_block
    return klass(values, ndim=ndim, placement=placement)
  File "C:\Users\LIAG8802\Documents\Procurement_analytics\venv\lib\site-packages\pandas\core\internals\blocks.py", line 2792, in __init__
    super().__init__(values, ndim=ndim, placement=placement)
  File "C:\Users\LIAG8802\Documents\Procurement_analytics\venv\lib\site-packages\pandas\core\internals\blocks.py", line 128, in __init__
    "{mgr}".format(val=len(self.values), mgr=len(self.mgr_locs))
ValueError: Wrong number of items passed 3, placement implies 0

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "C:\Users\LIAG8802\Documents\Procurement_analytics\venv\lib\site-packages\pandas\core\frame.py", line 3543, in _ensure_valid_index
    "Cannot set a frame with no defined index "
ValueError: Cannot set a frame with no defined index and a value that cannot be converted to a Series
如何知道代码中的哪一行导致了错误?请注意,我发现了问题所在,但我想知道如何更容易地追踪它


编辑:请注意,我无法在几行中跟踪问题,因为错误会在调试控制台中弹出,而不是在不会崩溃的
anaconda
控制台中弹出在不同的行中显示不同的消息,并查看哪一条消息将显示为错误之前的最后一条。@furas我想到了这一点,但问题是错误会在
破折号
调试控制台中弹出,而不是在不会崩溃的
蟒蛇
控制台中弹出。您能给出您编写的代码以便我们可以尝试重现错误吗?我会说这是由您输入的数据引起的panda错误,但我不能确定。@Frayal这似乎是因为我试图将空数据框保存到SQL表中,但我真正感兴趣的是这个回溯问题。回溯告诉您,在创建panda数据框(这里称为帧)时存在问题。数据帧的切片是一个序列。这些系列之间的链接是索引。如果无法设置索引或无法将数据切片为系列,pandas将引发错误。您可以在此处查看pd.DataFrame()的构建函数: