DataArray().drop_attrs(deep=False) doesn't do anything

[j-haacker]

[Edit] I didn't see any issue templates because I took the route via opening an issue linked to a line of code, which seems to have failed anyway.

I tried to drop DataArray attributes without dropping the coordinate attributes. For this, I set deep=False in the dataarray's method .drop_attrs(). This did not work.

Environment

INSTALLED VERSIONS
------------------
commit: None
python: 3.12.3 (main, Jan 17 2025, 18:03:48) [GCC 13.3.0]
python-bits: 64
OS: Linux
OS-release: 6.8.0-52-generic
machine: x86_64
processor: x86_64
byteorder: little
LC_ALL: None
LANG: en_US.UTF-8
LOCALE: ('en_US', 'UTF-8')
libhdf5: 1.14.2
libnetcdf: 4.9.4-development

xarray: 2025.1.1
pandas: 2.2.3
numpy: 2.2.2
scipy: 1.15.1
netCDF4: 1.7.2
pydap: None
h5netcdf: None
h5py: None
zarr: 3.0.1
cftime: 1.6.4.post1
nc_time_axis: None
iris: None
bottleneck: None
dask: 2025.1.0
distributed: None
matplotlib: 3.10.0
cartopy: 0.24.1
seaborn: None
numbagg: None
fsspec: 2024.12.0
cupy: None
pint: 0.24.4
sparse: None
flox: None
numpy_groupies: None
setuptools: 75.8.0
pip: 25.0
conda: None
pytest: 8.3.4
mypy: None
IPython: 8.31.0
sphinx: None

Minimal example to reproduce

import xarray as xr
a = xr.DataArray(0).assign_attrs({"b": "c"})
a = a.drop_attrs(deep=False)
print(a)

results in

<xarray.DataArray ()> Size: 8B
array(0)
Attributes:
    b:        c

The attributes should have been dropped but they are still present.

---

my initial guess

[Edit] removed, was wrong, see below

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[j-haacker]

I see now that should have opened the issue from the issues tab. If required, I can close this and open a new issue using the template.

[j-haacker]

My initial guess, that the dataarray attributes survived in a copy of itself, was wrong. I believe the answer is much simpler:

I believe that in

xarray/xarray/core/dataarray.py

Line 7579 in 160cced

self._to_temp_dataset().drop_attrs(deep=deep).pipe(self._from_temp_dataset)

_to_temp_dataset() wraps the variable in a Dataset, consequently .drop_attrs() only drops the dataset, but not the dataarray attributes if deep=False - see

xarray/xarray/core/dataset.py

Line 10931 in 160cced

if not deep:

[j-haacker]

I will leave it here because I can't think of a satisfying solution.

Allowing the argument deep to be a Literal meant to specify a depth level seems odd to me.

Changing Dataset().drop_attrs() to drop variable attributes, even with deep=False, would change the behavior in general and should not be done.

Using a new _to_temp_dataarray() method seems like an overkill.