Yes: it's a full introduction that starts from scratch and lots of people have used it to learn APL and say good things about it. I do recommend the online upda

Yes: it's a full introduction that starts from scratch and lots of people have used it to learn APL and say good things about it. I do recommend the online update, as a lot's changed since the original version was published. For completeness, the other book I might recommend is the more recent Learning APL (https://xpqz.github.io/learnapl/intro.html https://xpqz.github.io/learnapl/intro.html). My very biased opinion (as BQN's designer) is that it's easier to learn BQN and then APL instead of the other way around. BQN is more strict about a few things, which can avoid confusion, and APL's array model can be expressed as a modification of BQN's while the reverse is not possible. However, APL has quite a bit more material you can learn from. So I usually recommend trying the BQN tutorials and documentation, but switching to APL if you find you're not making progress.