"Conversion to int64 from py.numpy.ndarray is not possible." when using py2mat.m as illustrated in your pdf

[gpinardi]

Hello,

many thanks for this tool, which looks great. I am follwing step by step the illustrations you give in your pdf "python-for-matlab-development.pdf" (downloaded from here: https://www.matlabexpo.com/content/dam/mathworks/mathworks-dot-com/images/events/matlabexpo/online/2022/python-for-matlab-development.pdf)

I managed to reproduce everything up to slide 14, but I have a problem with:

double(z.get('x'))
Error using double
Conversion to double from py.numpy.ndarray is not possible.

I also have problems with py2mat (downloaded from here just now):

m = py2mat(z)
Error using int64
Conversion to int64 from py.numpy.ndarray is not possible.

Error in py2mat (line 98)
x_mat = int64(x_py.astype(np.float64));

Error in py2mat (line 67)
new_var = py2mat(x_mat.(fields{i}));

I am using the following versions, under linux:
Matlab version:

version
ans =
'9.9.0.1570001 (R2020b) Update 4'

python access, through:

pyenv
ans =
PythonEnvironment with properties:
Version: "3.9"
Executable: "/bira-iasb/softs/21g/py39/bin/python"
Library: "libpython3.9.so.1.0"
Home: "/bira-iasb/softs/21g/py39"
Status: Loaded
ExecutionMode: InProcess
ProcessID: "1515974"
ProcessName: "MATLAB"

Any clue?
Thanks!
Gaia

[gpinardi]

actually, by searching with some of the error messages that I got, I have found that this is related to some problems between matlab2020b and python3.9 (fooof-tools/fooof_mat#22)

I solved my problem by downgrading to Python 3.6.

[AlDanial]

Thanks for the follow-up post. You're on the right track; according to the compatibility table, 2020b only supports up to Python 3.8.