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Data export: `TypeError: Invalid value 'False' for dtype 'float64'`

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Assessment

Difficulty
2/5
Estimated time
1-3 hours
Newbie friendliness
72/100
Issue type
Bug
Clarity
Clearly specified
Activity status
Active
Tech stack
pandas, python
Domain
data

Research direction

Start in patzilla/navigator/export.py at prepare_dataframes() and inspect the df_documents['dismiss'].fillna(value=False, inplace=True) call shown in the traceback. Reproduce the export failure with the affected data and check how the dismiss column is represented before the fill. The issue is done when exporting the project to CSV and Workbook files no longer raises this dtype error.

Written by the indexing model from the issue text.

Description

bug

Problem

When exporting a project into CSV or Workbook files, we can observe an 500 Internal Server Error, because the application bailed out.

Details

2026-10-26 17:48:39,524 ERROR    [patzilla.navigator.services.util        ][waitress-3] Exporting format "xlsx" failed.. Exception:
Traceback (most recent call last):
  File "/path/to/site-packages/pandas/core/internals/blocks.py", line 1175, in putmask
    casted = np_can_hold_element(values.dtype, new)
  File "/path/to/site-packages/pandas/core/dtypes/cast.py", line 1792, in np_can_hold_element
    raise LossySetitemError
pandas.errors.LossySetitemError

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "/path/to/patzilla/patzilla/navigator/services/util.py", line 306, in export_util_handler
    payload = DossierXlsx(data).create()
              ~~~~~~~~~~~^^^^^^
  File "/path/to/patzilla/patzilla/navigator/export.py", line 474, in __init__
    super(DossierXlsx, self).__init__(data)
    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^^^^^^
  File "/path/to/patzilla/patzilla/navigator/export.py", line 55, in __init__
    self.prepare_dataframes()
    ~~~~~~~~~~~~~~~~~~~~~~~^^
  File "/path/to/patzilla/patzilla/navigator/export.py", line 113, in prepare_dataframes
    self.df_documents['dismiss'].fillna(value=False, inplace=True)
    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/path/to/site-packages/pandas/core/generic.py", line 7074, in fillna
    new_data = self._mgr.fillna(value=value, limit=limit, inplace=inplace)
  File "/path/to/site-packages/pandas/core/internals/managers.py", line 461, in fillna
    return self.apply(
           ~~~~~~~~~~^
        "fillna",
        ^^^^^^^^^
    ...<2 lines>...
        inplace=inplace,
        ^^^^^^^^^^^^^^^^
    )
    ^
  File "/path/to/site-packages/pandas/core/internals/managers.py", line 445, in apply
    applied = getattr(b, f)(**kwargs)
  File "/path/to/site-packages/pandas/core/internals/blocks.py", line 1342, in fillna
    nbs = self.putmask(mask.T, value)
  File "/path/to/site-packages/pandas/core/internals/blocks.py", line 1188, in putmask
    return self.coerce_to_target_dtype(
           ~~~~~~~~~~~~~~~~~~~~~~~~~~~^
        new, raise_on_upcast=True
        ^^^^^^^^^^^^^^^^^^^^^^^^^
    ).putmask(mask, new)
    ^
  File "/path/to/site-packages/pandas/core/internals/blocks.py", line 468, in coerce_to_target_dtype
    raise TypeError(f"Invalid value '{other}' for dtype '{self.values.dtype}'")
TypeError: Invalid value 'False' for dtype 'float64'
Dominant language
Python
Stars
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Forks
31
Avg merge
1h 9m
Merged PRs (30d)
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