ENH: Support `Resampler.mean(engine="numba")`

[donghyyun]

Pandas version checks

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• I have confirmed this bug exists on the latest version of pandas.

• I have confirmed this bug exists on the main branch of pandas.

Reproducible Example

import pandas as pd 

index = pd.date_range('1/1/2019', periods=12, freq='T')
series = pd.Series(range(12), index=index)

# Returns 'UnsupportedFunctionCall' error
series.resample("1T").mean(engine="numba")

Issue Description

Based on reference, I tried to apply numba engine to my code. However, faced an error as below

UnsupportedFunctionCall: numpy operations are not valid with resample. Use .resample(...).mean() instead

> UnsupportedFunctionCall Traceback (most recent call last) > Input In [15], in () > 4 series = pd.Series(range(12), index=index) > 6 # Returns 'UnsupportedFunctionCall' error > ----> 7 series.resample("1T").mean(engine="numba") > > File /opt/homebrew/Caskroom/miniforge/base/envs/onboarding/lib/python3.9/site-packages/pandas/core/resample.py:1100, in _add_downsample_kernel..f(self, numeric_only, *args, **kwargs) > 1097 def f( # type: ignore[misc] > 1098 self, numeric_only: bool | lib.NoDefault = lib.no_default, *args, **kwargs > 1099 ): > -> 1100 nv.validate_resampler_func(name, args, kwargs) > 1101 return self._downsample(name, numeric_only=numeric_only) > > File /opt/homebrew/Caskroom/miniforge/base/envs/onboarding/lib/python3.9/site-packages/pandas/compat/numpy/function.py:408, in validate_resampler_func(method, args, kwargs) > 406 if len(args) + len(kwargs) > 0: > 407 if method in RESAMPLER_NUMPY_OPS: > --> 408 raise UnsupportedFunctionCall( > 409 "numpy operations are not valid with resample. " > 410 f"Use .resample(...).{method}() instead" > 411 ) > 412 else: > 413 raise TypeError("too many arguments passed in") > > UnsupportedFunctionCall: numpy operations are not valid with resample. Use .resample(...).mean() instead

FYI: it works when run as below, but the output type is DataFrame with column name 'mean', not Series
series.resample("1T").agg(["mean"], engine="numba")

Expected Behavior

Same result as running series.resample("1T").mean() without an error
& Run through JIT compiled code from numba

Installed Versions

INSTALLED VERSIONS

commit : 87cfe4e
python : 3.9.13.final.0
python-bits : 64
OS : Darwin
OS-release : 21.4.0
Version : Darwin Kernel Version 21.4.0: Mon Feb 21 20:35:58 PST 2022; root:xnu-8020.101.4~2/RELEASE_ARM64_T6000
machine : arm64
processor : arm
byteorder : little
LC_ALL : None
LANG : None
LOCALE : None.UTF-8

pandas : 1.5.0
numpy : 1.22.4
pytz : 2022.2.1
dateutil : 2.8.2
setuptools : 65.3.0
pip : 22.2.2
Cython : None
pytest : None
hypothesis : None
sphinx : None
blosc : None
feather : None
xlsxwriter : None
lxml.etree : None
html5lib : None
pymysql : None
psycopg2 : None
jinja2 : 3.1.2
IPython : 8.4.0
pandas_datareader: None
bs4 : 4.11.1
bottleneck : None
brotli : None
fastparquet : None
fsspec : None
gcsfs : None
matplotlib : 3.5.3
numba : 0.55.2
numexpr : None
odfpy : None
openpyxl : None
pandas_gbq : None
pyarrow : None
pyreadstat : None
pyxlsb : None
s3fs : None
scipy : 1.9.0
snappy : None
sqlalchemy : 1.4.40
tables : None
tabulate : 0.8.10
xarray : None
xlrd : None
xlwt : None
zstandard : None
tzdata : None

[mroeschke]

Thanks for the report.

The numba engine hasn't be implemented for resample, just groupby and rolling so relabeling as an enhancement request.

Nonetheless, the error message is not entirely clear here

[donghyyun]

@mroeschke Thank you for the reply.

If numba engine is not supported in resample, I think the documentation should be revised.

And sorry for the unclear error message. The full error message is:

UnsupportedFunctionCall Traceback (most recent call last)
Input In [15], in <cell line: 7>()
4 series = pd.Series(range(12), index=index)
6 # Returns 'UnsupportedFunctionCall' error
----> 7 series.resample("1T").mean(engine="numba")

File /opt/homebrew/Caskroom/miniforge/base/envs/onboarding/lib/python3.9/site-packages/pandas/core/resample.py:1100, in _add_downsample_kernel..f(self, numeric_only, *args, **kwargs)
1097 def f( # type: ignore[misc]
1098 self, numeric_only: bool | lib.NoDefault = lib.no_default, *args, **kwargs
1099 ):
-> 1100 nv.validate_resampler_func(name, args, kwargs)
1101 return self._downsample(name, numeric_only=numeric_only)

File /opt/homebrew/Caskroom/miniforge/base/envs/onboarding/lib/python3.9/site-packages/pandas/compat/numpy/function.py:408, in validate_resampler_func(method, args, kwargs)
406 if len(args) + len(kwargs) > 0:
407 if method in RESAMPLER_NUMPY_OPS:
--> 408 raise UnsupportedFunctionCall(
409 "numpy operations are not valid with resample. "
410 f"Use .resample(...).{method}() instead"
411 )
412 else:
413 raise TypeError("too many arguments passed in")

UnsupportedFunctionCall: numpy operations are not valid with resample. Use .resample(...).mean() instead