https://en.wikipedia.org/wiki/SIMD
I'd say that slightly differently: J has been *implemented* as a single instruction multiple data language. There is nothing in the syntax of the language, nor in the dictionary description of the language, which prevents a multiple instruction implementation. And, in fact, this can be trivially achieved by using multiple J processes (perhaps on multiple machines). I say "trivially" because there are no portable language features which support this mode of operation. You need to deal with OS issues. Then again, having worked with other language environments - no matter what option you use, as you scale up things get messy and horrible, rather fast. Any new implementation will start out crippled and will sacrifice a variety of important features to achieve its gains. It's something of a miserable prospect. You chase perfection and you leave a mess in your wake. Hopefully a mess that some will find beautiful, but that's a matter of perspective. (If you can't tell, I am trying to psych myself up to carve another copy of Roger's work into little broken pieces in the hopes that this time I can put them back together in a somewhat useful fashion. In part, this is because of how broken the implementation winds up being on OpenBSD, and in part this is because of my perhaps dysfunctional perspective of How Things Should Work.) Good times... Thanks, -- Raul On Thu, Jan 8, 2015 at 9:00 AM, David Lambert <[email protected]> wrote: > J is a single data multi-instruction language. The trains and many of the > adverbs and conjunctions control data flow. enc2 is a hook. Below, find > where A appears in the explicit equivalent sentence. > > boxdraw_j_ 1 > > enc2 =: ;(</.~ 0 1 2 1 $~ #) > > enc2 A > +------------------+-----+---------+----+ > |hi ho how are you?|howeu|ih o r o?| hay| > +------------------+-----+---------+----+ > > A ; A </.~ (0 1 2 1"_ A) $~ # A > +------------------+-----+---------+----+ > |hi ho how are you?|howeu|ih o r o?| hay| > +------------------+-----+---------+----+ > >> Date: Thu, 08 Jan 2015 02:31:07 -0500 >> From: "Linda Alvord"<[email protected]> >> To:<[email protected]> >> Subject: Re: [Jprogramming] Rail Fence Cipher >> Message-ID:<[email protected]> >> Content-Type: text/plain; charset="koi8-r" >> >> This is odd, Pascal >> Remove @: in one situation and the results agree. However in a defined >> verb >> they don't agree. >> A=:'hi ho how are you?' >> enc =: ;@:(</.~ 0 1 2 1 $~ #) >> ;@:(</.~ (0 1 2 1 $~ #))A >> >> howeuih o r o? hay >> ;(</.~ (0 1 2 1 $~ #))A >> howeuih o r o? hay >> >> enc2 =: ;(</.~ 0 1 2 1 $~ #) >> >> enc2 A >> -------------------T-----T---------T----? >> ?hi ho how are you??howeu?ih o r o?? hay? >> L------------------+-----+---------+----- >> >> Linda >> >> >> -----Original Message----- >> From:[email protected] >> [mailto:[email protected]] On Behalf Of 'Pascal >> Jasmin' via Programming >> Sent: Wednesday, January 7, 2015 11:43 PM >> To: Programming forum >> Subject: [Jprogramming] Rail Fence Cipher >> > > ---------------------------------------------------------------------- > For information about J forums see http://www.jsoftware.com/forums.htm ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm
