@loke @ckeen Maybe http://www.softwarepreservation.org/projects/apl/Manuals/AnIntroductionToAPLForScientistsAndEngineers can be useful. Also the APL ISO standard is probably the most authorative reference, but not free.
@alexshendi @ckeen You should be able to use the US keymap, and simply switch to that one when using APL. When adding more than one keymap you will have a panel button that allows you too select which one to activate.
Personally, I don't do that since I do all my APL stuff in Emacs. I designed the Emacs keymap for US keyboard, but adjusting it for German would be trivial.
If you do this, I'd be happy to include it in the Emacs mode (I was the one two wrote it).
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