For the MSc Computer Science program at ETH, you can assign your grades to different categories in myStudies. However, because your final GPA is calculated as a weighted average of a few select subcategory averages, and because some courses can potentially be assigned to several categories, it might be confusing to figure out the way to get the best grade.
Fear not! Just exhaustively search all the combinations!
If you'd like to use this script, edit optimize.py to insert your own grades and courses, then run it and find out the results! If someone wants to make a pull request, e.g. to prune the exhaustive search, scrape myStudies, or make this otherwise more user-friendly, go ahead.