I came across J/K/APL a few months ago while working my way through some project euler problems, and was intrigued, to say the least. For every elegant-looking 20 line python solution I produced, there'd be a gobsmacking 20 character J solution that ran in a tenth of the time. I've been keen to learn some basic J, and have made a few attempts at picking up the vocabulary, but have found the learning curve to be quite steep.
To those who are familiar with these languages, would you recommend investing some time to learn one (I'm thinking J in particular)? I would do so more for the purpose of satisfying my curiosity than for career advancement or some such thing.
Some personal circumstances to consider, if you care to:
I love mathematics, and use it daily in my work (as a mathematician for a startup) but to be honest I don't really feel limited by the tools that I use (like python + NumPy) so I can't use that excuse.
I have no particular desire to work in the finance industry, which seems to be the main port of call for K users at least. Plus I should really learn C# as a next language as it's the primary language where I work. So practically speaking, J almost definitely shouldn't be the next language I learn.
I'm reasonably familiar with MATLAB so using an array-based programming language wouldn't constitute a tremendous paradigm shift.
Any advice from those familiar with these languages would be much appreciated.