Description
Describe your issue.
When accessing the nit attribute in the callback function of a scipy.optimize.minimze call, it raises an attribute error, although it's stated in the documentation of OptimizeResult that nit exists and is equal to the number of iterations performed by the optimizer.
Reproducing Code Example
from scipy.optimize import minimize
import numpy as np
def objective(x):
return np.sum((x - 1)**2)
def callback(intermediate_result):
print(intermediate_result.nit)
minimize(objective, np.array([5, 5]), callback=callback)Error message
Traceback (most recent call last):
File "/work/draft/.env/lib/python3.11/site-packages/scipy/_lib/_util.py", line 1091, in __getattr__
return self[name]
~~~~^^^^^^
KeyError: 'nit'
The above exception was the direct cause of the following exception:
Traceback (most recent call last):
File "/work/draft/draft.py", line 10, in <module>
minimize(objective, np.array([5, 5]), callback=callback)
File "/work/draft/.env/lib/python3.11/site-packages/scipy/optimize/_minimize.py", line 733, in minimize
res = _minimize_bfgs(fun, x0, args, jac, ca
7AB2
llback, **options)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/work/draft/.env/lib/python3.11/site-packages/scipy/optimize/_optimize.py", line 1440, in _minimize_bfgs
if _call_callback_maybe_halt(callback, intermediate_result):
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/work/draft/.env/lib/python3.11/site-packages/scipy/_lib/_util.py", line 1080, in _call_callback_maybe_halt
callback(res)
File "/work/draft/.env/lib/python3.11/site-packages/scipy/optimize/_optimize.py", line 97, in wrapped_callback
return callback(intermediate_result=res)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/work/draft/draft.py", line 8, in callback
print(intermediate_result.nit)
^^^^^^^^^^^^^^^^^^^^^^^
File "/work/draft/.env/lib/python3.11/site-packages/scipy/_lib/_util.py", line 1093, in __getattr__
raise AttributeError(name) from e
AttributeError: nitSciPy/NumPy/Python version and system information
1.15.3 2.2.5 sys.version_info(major=3, minor=11, micro=2, releaselevel='final', serial=0)
Build Dependencies:
blas:
detection method: pkgconfig
found: true
include directory: /opt/_internal/cpython-3.11.10/lib/python3.11/site-packages/scipy_openblas32/include
lib directory: /opt/_internal/cpython-3.11.10/lib/python3.11/site-packages/scipy_openblas32/lib
name: scipy-openblas
openblas configuration: OpenBLAS 0.3.28 DYNAMIC_ARCH NO_AFFINITY Haswell MAX_THREADS=64
pc file directory: /project
version: 0.3.28
lapack:
detection method: pkgconfig
found: true
include directory: /opt/_internal/cpython-3.11.10/lib/python3.11/site-packages/scipy_openblas32/include
lib directory: /opt/_internal/cpython-3.11.10/lib/python3.11/site-packages/scipy_openblas32/lib
name: scipy-openblas
openblas configuration: OpenBLAS 0.3.28 DYNAMIC_ARCH NO_AFFINITY Haswell MAX_THREADS=64
pc file directory: /project
version: 0.3.28
pybind11:
detection method: config-tool
include directory: unknown
name: pybind11
version: 2.13.6
Compilers:
c:
commands: cc
linker: ld.bfd
name: gcc
version: 10.2.1
c++:
commands: c++
linker: ld.bfd
name: gcc
version: 10.2.1
cython:
commands: cython
linker: cython
name: cython
version: 3.0.12
fortran:
commands: gfortran
linker: ld.bfd
name: gcc
version: 10.2.1
pythran:
include directory: ../../tmp/pip-build-env-4uho68t1/overlay/lib/python3.11/site-packages/pythran
version: 0.17.0
Machine Information:
build:
cpu: x86_64
endian: little
family: x86_64
system: linux
cross-compiled: false
host:
cpu: x86_64
endian: little
family: x86_64
system: linux
Python Information:
path: /opt/python/cp311-cp311/bin/python
version: '3.11'