Description
Pandas version checks
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I have checked that this issue has not already been reported.
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I have confirmed this bug exists on the latest version of pandas.
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I have confirmed this bug exists on the main branch of pandas.
Reproducible Example
import numpy as np
import pandas as pd
N = 10
hash_dtype = np.dtype([(f'h{i}', np.uint64) for i in range(4)])
hashes = np.zeros(N, dtype=hash_dtype)
df = pd.DataFrame(data={'hashes':hashes, 'other_stuff':np.zeros(N)})
idx = [0, 1]
## This fails
df.loc[idx, 'hashes'] = np.ones(len(idx), dtype=hash_dtype)
# LossySetitemError:
# During handling of the above exception, another exception occurred:
# AssertionError
# AssertionError: Something has gone wrong, please report a bug at https://github.com/pandas-dev/pandas/issues
## This also files
print(df)
# TypeError: ufunc 'isnan' not supported for the input types, and the inputs could not be safely coerced to any supported types according to the casting rule ''safe''
## This is ok
print(df['other_stuff'])
## This is a partial workaround
df['hashes'] = np.zeros(len(df), dtype=hash_dtype) # same errors with or without this line
df['hashes'].values[idx] = np.ones(len(idx), dtype=hash_dtype)
## But things still broken
print(df['hashes'])
# TypeError: ufunc 'isnan' not supported for the input types, and the inputs could not be safely coerced to any supported types according to the casting rule ''safe''
## This works
print(df.loc[0, 'hashes'])
## This doesn't
print(df.loc[:, 'hashes'])
# TypeError: ufunc 'isnan' not supported for the input types, and the inputs could not be safely coerced to any supported types according to the casting rule ''safe''
## OK
x = df['hashes']
## Not OK
x = df[['hashes', 'other_stuff']]
# TypeError: void() takes at least 1 positional argument (0 given)Issue Description
Working with a numpy array with a structured type consisting of four 64 bit integers, there are various errors when getting/setting the associated data in a dataframe.
- Trying to set values with
df.loc[idx, 'hashes'] =get LossySetitemError, AssertionError: Something has gone wrong - can work-around by directly indexing into the underlying array
df['hashes'].values[idx] =(but for other indexes would have to do something likedf['hashes'].values[df.index.isin(idx)] =or usedf.index.get_indexer) - printing/string reps broken, e.g.
print(df)andprint(df['hashes']) - trying to access
df[['hashes', 'other_stuff']]TypeError: void() takes at least 1 positional argument (0 given)
Expected Behavior
can set values with .loc without assertion error
can print dataframe without exception
Installed Versions
INSTALLED VERSIONS
commit : 0691c5c
python : 3.12.7
python-bits : 64
OS : Linux
OS-release : 6.6.57-1-lts
Version : #1 SMP PREEMPT_DYNAMIC Thu, 17 Oct 2024 13:57:25 +0000
machine : x86_64
processor :
byteorder : little
LC_ALL : None
LANG : en_US.UTF-8
LOCALE : en_US.UTF-8
pandas : 2.2.3
numpy : 2.1.2
pytz : 2024.2
dateutil : 2.9.0.post0
pip : 24.2
Cython : 3.0.11
sphinx : None
IPython : 8.28.0
adbc-driver-postgresql: None
adbc-driver-sqlite : None
bs4 : 4.12.3
blosc : None
bottleneck : None
dataframe-api-compat : None
fastparquet : None
fsspec : None
html5lib : None
hypothesis : None
gcsfs : None
jinja2 : None
lxml.etree : 5.3.0
matplotlib : 3.9.2
numba : None
numexpr : None
odfpy : None
openpyxl : 3.1.5
pandas_gbq : None
psycopg2 : None
pymysql : None
pyarrow : None
pyreadstat : None
pytest : None
python-calamine : None
pyxlsb : None
s3fs : None
scipy : 1.14.1
sqlalchemy : None
tables : None
tabulate : None
xarray : None
xlrd : 2.0.1
xlsxwriter : 3.1.9
zstandard : 0.22.0
tzdata : 2024.2
qtpy : 2.4.1
pyqt5 : None