"oserror: [winerror 126] The Specified Module Could Not Be Found" Using Pvfactors Library

I started using the pvfactors tool in Python (which calculates the irradiance incident on surfaces of a photovoltaic arrays) following the website tutorial 1. import numpy as np im

Solution 1:

the 2nd to last line:

anaconda3\lib\site-packages\shapely\geos.py", line 154, in _lgeos = CDLL(os.path.join(sys.prefix, 'Library', 'bin', 'geos_c.dll'))

shows that your python cannot find the GEOS library that Shapely uses. Shapely is a dependency in pvfactors. However it appears your anaconda environment does have Shapely installed, so there is something wrong either with anaconda or your conda environment. The solution for this is almost always to create a new environment and activate it. Part of the problem is that pvfactors is only distributed in PyPI, and doesn't have a conda forge or anaconda package, so you have to install the requirements from Anaconda manually. Luckily Shapely is on conda forge

Try this in an anaconda prompt (enter commands after C:\Users\karen\> ):

(base) C:\Users\karen\> conda create -n myenv(base) C:\Users\karen\> activate myenv(myenv) C:\Users\karen\> conda config --env --add channels conda-forge
(myenv) C:\Users\karen\> conda install python pvlib-python shapely matplotlib future six(myenv) C:\Users\karen\> pip install --no-deps pvfactors(myenv) C:\Users\karen\> conda install <other stuff like ipython Jupyter spyder etc>

Good luck. I would recommend creating an issue in pvfactors and ask them to add a conda forge package.

PS: see https://docs.conda.io/projects/conda/en/latest/commands/config.html PPS: see https://pip.pypa.io/en/stable/reference/pip_install/#install-no-deps