https://github.com/UG4/ugcore provides a short introduction to several example scripts (with pictures).
Once you compiled UG4 you may execute the script like this:
bash cd ug4/runs ugshell -ex Examples/reverseOsmosis.lua -stokes
Very first steps with UG4 g++ compiler is required: sudo apt-get install g++
bash sudo apt-get install libopenblas-dev liblapack-de
http://ug4.github.io/docs/index.html http://www.sppexa.de/fileadmin/user_upload/Teachlets/exasolvers_ug4.pdf
where to find toturials? http://ug4.github.io/docs/page_script_tutorial.html
The following bibliography is recommended for citation and must be preserved in all covered files: "Reiter, S., Vogel, A., Heppner, I., Rupp, M., and Wittum, G. A massively parallel geometric multigrid solver on hierarchically distributed grids. Computing and visualization in science 16, 4 (2013), 151-164" "Vogel, A., Reiter, S., Rupp, M., Nägel, A., and Wittum, G. UG4 -- a novel flexible software system for simulating pde based models on high performance computers. Computing and visualization in science 16, 4 (2013), 165-179"