I try to solve my problem asked on stackoverflow about a python script which uses TeX to create matplotlib labels. see https://stackoverflow.com/questions/50875637/matplotlib-how-do-i-have-to-provide-font-metrics-files-for-rendering-text-by-te for details.
It turns out that a tfm file is missing.
FileNotFoundError: missing font metrics file: rsfs10
However, the package rsfs is installed, but the package does not contain the tfm files. https://ctan.org/tex-archive/fonts/rsfs/
Is there any reason for that? Where could I get such tfm file?
I already found a similar topic: Problem finding metafonts at compilation
The solution which was provided there, was the installation of the package. But this is already done on my system.
Best Answer
With the help of the discussion of my question (see comments), I found a solution:
On my computer, the MikTex installation was quite new, and the font has never been used before, therefore the required tfm files had not been created.
However, the matplotlib Python package (dviread.py) tried to identify the tfm files before usage in order to create a fontfile cache (see question here https://stackoverflow.com/questions/50875637/matplotlib-how-do-i-have-to-provide-font-metrics-files-for-rendering-text-by-te)
I have installed a complete TeXLive installation on another computer. There the tfm files were already created during installation and I just copied the files to the corresponding location on my computer.