CMA-ES The default example contains an issue.

[jchahal-wiio]

Hello,

Firstly, a big thanks for this library! It is very useful.

When I run the example of CMA-ES (https://pymoo.org/algorithms/soo/cmaes.html) :

import numpy as np
from pymoo.algorithms.soo.nonconvex.cmaes import CMAES
from pymoo.problems import get_problem
from pymoo.optimize import minimize

problem = get_problem("sphere")

algorithm = CMAES(x0=np.random.random(problem.n_var))

res = minimize(problem,
               algorithm,
               seed=1,
               verbose=False)

print(f"Best solution found: \nX = {res.X}\nF = {res.F}\nCV= {res.CV}")

I have this error:

File "[...]\CMA_ES.py", line 11, in <module>
  res = minimize(problem,
        ^^^^^^^^^^^^^^^^^
File "[...]\.venv\Lib\site-packages\pymoo\optimize.py", line 67, in minimize
  res = algorithm.run()
        ^^^^^^^^^^^^^^^
File "[...]\.venv\Lib\site-packages\pymoo\core\algorithm.py", line 138, in run
  self.next()
File "[...]\.venv\Lib\site-packages\pymoo\core\algorithm.py", line 159, in next
  self.advance(infills=infills)
File "[...]\.venv\Lib\site-packages\pymoo\core\algorithm.py", line 214, in advance
  self._initialize_advance(infills=infills, **kwargs)
File "[...]\.venv\Lib\site-packages\pymoo\algorithms\soo\nonconvex\cmaes.py", line 431, in _initialize_advance
  self.next_X = next(self.es)
                ^^^^^^^^^^^^^
File "[...]\.venv\Lib\site-packages\pymoo\vendor\vendor_cmaes.py", line 128, in my_fmin
  es = MyCMAEvolutionStrategy(x0, sigma_factor * sigma0, opts)
       ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "[...]\.venv\Lib\site-packages\cma\evolution_strategy.py", line 1503, in __init__
  self.boundary_handler = self.boundary_handler(opts['bounds'])
                          ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "[...]\.venv\Lib\site-packages\cma\constraints_handler.py", line 259, in __init__
  self.bounds_tf = BoxConstraintsLinQuadTransformation(self.to_dim_times_two(bounds))
                   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "[...]\.venv\Lib\site-packages\cma\transformations.py", line 262, in __init__
  super(BoxConstraintsLinQuadTransformation, self).__init__(bounds)
File "[...]\.venv\Lib\site-packages\cma\transformations.py", line 123, in __init__
  self.initialize()
File "[...]\.venv\Lib\site-packages\cma\transformations.py", line 271, in initialize
  self._lb = array([self.bounds[min((i, max_i))][0]
             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
ValueError: Unable to avoid copy while creating an array as requested.
If using `np.array(obj, copy=False)` replace it with `np.asarray(obj)` to allow a copy when needed (no behavior change in NumPy 1.x).
For more details, see https://numpy.org/devdocs/numpy_2_0_migration_guide.html#adapting-to-changes-in-the-copy-keyword.

I'm on Windows 11, with python 3.12 and with this pip environment :

Package         Version
--------------- -----------
about-time      4.2.1
alive-progress  3.1.5
autograd        1.7.0
cma             3.2.2
contourpy       1.3.0
cycler          0.12.1
Deprecated      1.2.14
dill            0.3.9
fonttools       4.54.1
grapheme        0.6.0
kiwisolver      1.4.7
matplotlib      3.9.2
networkx        3.4.1
numpy           2.1.2
packaging       24.1
pillow          11.0.0
pip             23.2.1
pygame          2.6.1
pymoo           0.6.1.3
pyparsing       3.2.0
python-dateutil 2.9.0.post0
scipy           1.14.1
six             1.16.0
wrapt           1.16.0

Is anyone can help me fixing this issue? Thanks in advance!

[blankjul]

what version of cma are you using? did you install it coming along with the pymoo package?

[jchahal-wiio]

Thank you for your feedback!
As shown in the pip list, the current cma version is 3.2.2, which is the default version included with the latest pymoo installation (0.6.1.3).
If you have any further questions, please don’t hesitate to reach out!