Have you used Dyalog APL recently? They now have a rank operator and fork/hook from J. I am learning J but haven't made up my mind about this.

Dyalog appears to be more popular with conferences and more products, but it costs $1k ish for a commercial license and nobody else can run your code without a license and server licenses aren't cheap. It also pretty much needs a special keyboard and a key mapping. J is free for pretty much everything and uses standard characters (although I really like the APL characters). I think they're both nice.

Dyalog comes with a keyboard layout (on a Mac it just replaces the alt keys). It's quite easy to use. GNU APL's Emacs mode does the same thing, although mapped to super rather than alt (meta, in Emacs) by default.

I'm aware of the licensing costs, I'm more curious about whether Dyalog is obtaining popularity versus J, and if so, why. Of course, three new people going to the Dyalog conference would be a 10% increase in popularity, it looks like… so maybe this far out on the long tail it doesn't matter.

Yea, I was just saying the key mappings can be a pain and your favorite keyboard probably doesn't have the APL symbols on it. The Dyalog IDE has a virtual keyboard, but I don't like those too much. If none of that bothers you, than no biggie. I'm guessing Dyalog has more production users and a bit more users than you see at the conference as they are typically held in the UK. J is free, so I bet a lot more people try it even though Dyalog has a free hobby license. J has a nice built in plotting library"viewmat" while Dyalog has sharpleaf. Both are nice, but sharpleaf has a GUI like doing charts in Excel. Dyalog can easily hook-in to .NET, so that is pretty helpful on Windows in the real-world. I'd agree it's a wash right now. What is your background and needs?

My background is I know too many languages and don't get enough shit done and my need is probably to stop it and get back to work. :)

Being slightly more serious, I do web dev, mostly backend, for a radio astronomy observatory. I don't know anything about the science, but I wind up executing their routines in the cluster and doing typical database apps. I don't have much time on the side but I have been enjoying trying to learn J and realizing how much applied math is missing in my background!

I also dabble in Dyalog APL. I have an inexplicable bias for the symbols, however I really like J and the commmunity. I have played with Jd with a trial license, and as said above, J is free and the source is available for scrutiny. I have played with using the J DLLs in my C code. I am always amazed at my takeaway understanding of a mathematics problem after working it out in J. It somehow gels it in my mind, and fits with the equations in normal math symbols.

I am one of those who stare at arrays! [1]

  [1]  http://www.aprogramminglanguage.com/

I like the APL symbols, but I think we could probably do better today, since we're not as limited by what we can come up with using overstriking.

Probably, but like Cuneiform's wedge-shaped marks, it brings an easy familiarity to a line or lines of text or code. It would be cool to make APl in Vulcan or Predator symbols!

Haha...I'm in the same boat and need to stick with one.

I'm more comfortable in J but there are design choices in K that really appeal to me.

My ideal language would be K's function syntax and k-tree data structure/namespaces, but with J's primitives and standard library.