Install pymc issues

Dear All,

I have too much tried to come up with a solution regarding my installation issue. I have python version Python 3.8.5 and installed pymc version of 5.4.1. After running just the following code line to import pymc library (import pymc as pm) I recieved the following errors and warning. I would be thankful if you help.

WARNING (pytensor.configdefaults): g++ not available, if using conda: conda install m2w64-toolchain
WARNING (pytensor.configdefaults): g++ not detected! PyTensor will be unable to compile C-implementations and will default to Python. Performance may be severely degraded. To remove this warning, set PyTensor flags cxx to an empty string.
Traceback (most recent call last):

NoSectionError: No section: ‘blas’
KeyError: ‘blas__ldflags’
FileNotFoundError: [WinError 3] Das System kann den angegebenen Pfad nicht finden: ‘D:\a\1\s\numpy\build\openblas_info’


How did you install PyMC? Did you follow the official installation instructions?


I have installed the the package via console of spyder. I followed the instruction that you have provided however, it does not work and I recieved the message above

Can you share what platform you are on (windows, macOS, linux) and the output when running conda list?

Hey Faramarz. i recently helped a coworker/friend install pymc. i’m on windows and struggled installing it so these are the instructions i gave him.

step 0: install miniconda. Miniconda — conda documentation
miniconda is barebones conda. once it is installed. open up conda. ( Anaconda Prompt (miniconda3) )

  1. conda create -c conda-forge -n pymc_env “pymc>=5” python=3.10.6
  2. activate pymc_env
    get in.
  3. pip install numba (inside your pymc_env)
  4. conda install -c conda-forge mamba (inside your pymc_env)
  5. mamba install -c conda-forge nutpie pymc (inside your pymc_env)

i specified python=3.10.6 this is what is working for me. a month ago numba didn’t have support for python 3.11 (i think now it does?? but you’ll have to test it yourself, so just use 3.10.6).

once everything is setup you can pip install jupyter notebook. jupyter lab or anything else that you use. i dont recommend spyder, haven’t used it in years. VS-code user.

1 Like

Hi all, I have got the same problem recently. While using archlinux, the newest version of numpy (1.26.0) caused the error message about not finding blas. However, downgrading the numpy to 1.25.2 resolved the issue