I learned APL on a mainframe over 30 years ago, which is not something I'd recommend (also, you're unlikely to have access to one), but rumor says Dyalog has go

I learned APL on a mainframe over 30 years ago, which is not something I'd recommend (also, you're unlikely to have access to one), but rumor says Dyalog has good tutorials, such as "Mastering Dyalog APL", see links here https://www.dyalog.com/getting-started.htm https://www.dyalog.com/getting-started.htm As for K, Stefan Kruger's text seems like a good introduction https://xpqz.github.io/kbook/Introduction.html https://xpqz.github.io/kbook/Introduction.html