'''[http://www.jsoftware.com/%|%J]''' is a modern, freely-licensed descendant
of [APL]



** See Also **

   [http://www.sigapl.org/%|%SIGPLAN Chapter on Array Programming Languages]:   

   [An APL playstation]:   rolled by [RS].  Need one Unicoded APL font, and [Tk] of course...

   [Tacit programming]:   some J code examples, and how to replay them in Tcl



** Description **

I have only used [APL] but I understand J is a newer version that removes the
need for the APL font which was always a bane of any installation. Yet, it
seems strange for this to happen in the days of Unicode and graphics displays.
I don't think it makes it any easier to read though.

For an example of of how to configure a unicode environment to get [APL]
characters on your keyboard and have them display properly, see [An APL
playstation].

[[There are many versions of J, the early versions are freely distributable in
source, http://www.math.uwaterloo.ca/~ljdickey/#apl-j is a good resource.  More
recent versions are freely available only in binary form under a non-commercial
license, http://www.jsoftware.com is the resource here.  One thing which
distinguishes J from other languages in the APL family is that Ken Iverson --
the guy who invented APL (to make it possible to document the IBM 360
architecture, back in the early 1960s) -- is also the architect behind J.]]

Also of possible interest is a writeup on '''A'''
[http://www.vector.org.uk/aflat/history.htm] -- the implementation of A was
important in getting J off the ground.  Unfortunately, that page is a bit hard
to read, because it expects that you have a special font installed with implied
special character mappings -- they should have used gif images to represent
those characters.  Also, it's a bit old -- while that page claims that A+ "is
is quite definitely not for sale", A+ is now distributed under the terms of the
GPL .



<<categories>> Programming Language