BUG: np.fft.hfft results differ from previous release when n > len(arr) #25679
Description
Describe the issue:
I'm not sure whether this is related to #25661, but this is an incorrect output rather than a segfault, so I thought I'd file a separate issue.
Reproduce the code example:
import numpy as np
print(f"{np.__version__=}")
x = np.arange(5) + 1j * np.ones(5)
print(np.fft.hfft(x, n=10))Error message:
Output with numpy 1.23.5
np.__version__='1.23.5'
[ 20. 0.68323112 -5. 4.92522101 -5.
4. -5. 2.0190509 -5. -11.62750303]
Output with recent nightly build:
np.__version__='2.0.0.dev0+git20240123.877ca75'
[ 20. -0.49233939 -3.09788697 3.02310798 -3.8244295
4. -6.1755705 3.92116393 -6.90211303 -10.45193252]
I would expect these outputs to be consistent across numpy versions.
Python and NumPy Versions:
>>> import sys, numpy; print(numpy.__version__); print(sys.version)
2.0.0.dev0+git20240120.6bd3abf
3.9.6 (default, May 7 2023, 23:32:44)
[Clang 14.0.3 (clang-1403.0.22.14.1)]Runtime Environment:
>>> import numpy; print(numpy.show_runtime())
[{'numpy_version': '2.0.0.dev0+git20240120.6bd3abf',
'python': '3.9.6 (default, May 7 2023, 23:32:44) \n'
'[Clang 14.0.3 (clang-1403.0.22.14.1)]',
'uname': uname_result(system='Darwin', node='jmdg-macbookpro.roam.internal', release='23.2.0', version='Darwin Kernel Version 23.2.0: Wed Nov 15 21:53:18 PST 2023; root:xnu-10002.61.3~2/RELEASE_ARM64_T6000', machine='arm64')},
{'simd_extensions': {'baseline': ['NEON', 'NEON_FP16', 'NEON_VFPV4', 'ASIMD'],
'found': ['ASIMDHP'],
'not_found': ['ASIMDFHM']}}]Context for the issue:
No response