5 ms·

Is anyone using J as a component in a "modern" application? I am looking for an excuse to learn the language, but my current projects are more traditional web a

Is anyone using J as a component in a "modern" application? I am looking for an excuse to learn the language, but my current projects are more traditional web applications. I could likely find an excuse for it in data analysis/manipulation, but that seems like the obvious application.

Jtsummers 13y ago
Once upon a time, around 8 years ago, I gave J a serious go as a hobby language. At the time I was subscribed to their mailing lists, they were very active and a quick perusal suggests they're still active. If you want to know more about what people are using it for I'd highly recommend checking out the archives or asking them directly. Data manipulation and visualization seemed to be big topics at the time. Many of the posts in the mailing list seemed to come from individuals who programmed only as a hobby or where it wasn't their actual job. They programmed to do work, but were not programmers for work (think accountants, teachers and the like, solving some receptive task with a program they put together rather than doing the mundane over and over and over again). [1] http://www.jsoftware.com/forums.htm http://www.jsoftware.com/forums.htm - the one called "programming" is what you'll be interested in.
klibertp 13y ago
I used J exactly for data manipulation[2] - it was really neat even for very simple things like grouping and aggregating rows of a table (or columns). The terseness of J makes it very well suited for interactive, incremental development; very unusual semantics of functions (monadic vs. dyadic, verbs vs. nouns vs. gerunds) make the language very composable. It's also pure - at least outside of special, implementation provided functions. And it's fast. A typical script for reading a CSV file, manipulating it in some more or less complex way and dumping results back to file would take ~40 lines of Python (with native lists and csv module from stdlib), ~25 lines of Python with Pandas and about 5 lines of J. It obviously doesn't matter if the script is going to last for years, but if it's going to be used a few times and discarded[1], then working with J is a considerable advantage. One thing of note, though: J is HARD. It's unlike any other language you could know and it's moderately complex. It's not that hard to pick up the basics - although my head exploded a few times before I understood how J even parses expressions - but it's entirely non-trivial to learn how the basic building blocks compose to enable you to do something useful. In my experience there's just no shortcut here - you need to start with basics and slowly work your way up. It took me a couple of weeks of learning in the evenings to get J enough to actually do something, but then it rapidly became very simple (both to do things and to learn more of J). If you don't know any array-based language, I'd say give J a chance. Even if you won't use it itself very often, you'll learn some valuable skills, transferable to Python/Pandas or R. And if you do use it, you'll get significant boost in speed of development. [1] Actually, J is not "write-only" language, it's just not meant to be read without the help of J environment. Reading J consists of pasting pieces of definitions into REPL and experimenting with them, and possibly using one of a few built-in ways to analyse the definition structure. [2] Also for solving fizz-buzz: http://livescript.net/blog/fizzbuzzbazz.html#comment-1145818066 http://livescript.net/blog/fizzbuzzbazz.html#comment-1145818...
ProfVitzli 13y ago
I think everybody who is using APL would have good reasons to use J (which is actually APL's successor and was also created by Ken Iverson). If one is interested in these kind of languages, he should definitely also check out Arthur Whitney's magnificent K and Q (https://en.wikipedia.org/wiki/K_%28programming_language%29 https://en.wikipedia.org/wiki/K_%28programming_language%29).
- klibertp 13y ago
  I'm not sure, but I think I heard they are not open source?
- alexcash 13y ago
  If you want to try out q there's a similar video available for it here: http://www.timestored.com/kdb-guides/getting-started-kdb http://www.timestored.com/kdb-guides/getting-started-kdb q isn't open source but it is widely used by most major banks to analyse their time series data and there are very well paying and interesting jobs available.

Jtsummers 13y ago

Once upon a time, around 8 years ago, I gave J a serious go as a hobby language. At the time I was subscribed to their mailing lists, they were very active and a quick perusal suggests they're still active. If you want to know more about what people are using it for I'd highly recommend checking out the archives or asking them directly. Data manipulation and visualization seemed to be big topics at the time. Many of the posts in the mailing list seemed to come from individuals who programmed only as a hobby or where it wasn't their actual job. They programmed to do work, but were not programmers for work (think accountants, teachers and the like, solving some receptive task with a program they put together rather than doing the mundane over and over and over again). [1] http://www.jsoftware.com/forums.htm http://www.jsoftware.com/forums.htm - the one called "programming" is what you'll be interested in.

klibertp 13y ago

I used J exactly for data manipulation[2] - it was really neat even for very simple things like grouping and aggregating rows of a table (or columns). The terseness of J makes it very well suited for interactive, incremental development; very unusual semantics of functions (monadic vs. dyadic, verbs vs. nouns vs. gerunds) make the language very composable. It's also pure - at least outside of special, implementation provided functions. And it's fast. A typical script for reading a CSV file, manipulating it in some more or less complex way and dumping results back to file would take ~40 lines of Python (with native lists and csv module from stdlib), ~25 lines of Python with Pandas and about 5 lines of J. It obviously doesn't matter if the script is going to last for years, but if it's going to be used a few times and discarded[1], then working with J is a considerable advantage. One thing of note, though: J is HARD. It's unlike any other language you could know and it's moderately complex. It's not that hard to pick up the basics - although my head exploded a few times before I understood how J even parses expressions - but it's entirely non-trivial to learn how the basic building blocks compose to enable you to do something useful. In my experience there's just no shortcut here - you need to start with basics and slowly work your way up. It took me a couple of weeks of learning in the evenings to get J enough to actually do something, but then it rapidly became very simple (both to do things and to learn more of J). If you don't know any array-based language, I'd say give J a chance. Even if you won't use it itself very often, you'll learn some valuable skills, transferable to Python/Pandas or R. And if you do use it, you'll get significant boost in speed of development. [1] Actually, J is not "write-only" language, it's just not meant to be read without the help of J environment. Reading J consists of pasting pieces of definitions into REPL and experimenting with them, and possibly using one of a few built-in ways to analyse the definition structure. [2] Also for solving fizz-buzz: http://livescript.net/blog/fizzbuzzbazz.html#comment-1145818066 http://livescript.net/blog/fizzbuzzbazz.html#comment-1145818...

ProfVitzli 13y ago

I think everybody who is using APL would have good reasons to use J (which is actually APL's successor and was also created by Ken Iverson). If one is interested in these kind of languages, he should definitely also check out Arthur Whitney's magnificent K and Q (https://en.wikipedia.org/wiki/K_%28programming_language%29 https://en.wikipedia.org/wiki/K_%28programming_language%29).

klibertp 13y ago
I'm not sure, but I think I heard they are not open source?
alexcash 13y ago
If you want to try out q there's a similar video available for it here: http://www.timestored.com/kdb-guides/getting-started-kdb http://www.timestored.com/kdb-guides/getting-started-kdb q isn't open source but it is widely used by most major banks to analyse their time series data and there are very well paying and interesting jobs available.