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----- Original Message -----
From: Matthew Brand <[email protected]>
Date: Tuesday, May 26, 2009 6:58
Subject: Re: [Jchat] No More APL
To: Chat forum <[email protected]>

> What are the benefits of choosing APL over J if you do not know either
> to begin with?
> 
> Let's not mention the ascii vs non-ascii character set (that has been
> done to death by now!) or the cost, I want to know about comparisons
> of what you can practically do with them and how easy it is to do
> those things.
> 
> Is there a particular algorithm that anybody knows that is
> significantly easier to write or which executes "better" in J than
> APL?
> 
> I have never used APL but I gather from what I read that there are
> more inconsistencies in the language of APL compared to J, but that
> there are more libraries available for APL.
> 
> 
> 
> On Tue, May 26, 2009 at 11:04 AM, Morten Kromberg 
> <[email protected]> wrote:
> > Hi Ian!
> >
> > Your subject line caught my eye... ;-) And since you're 
> posting old news
> > about Dyalog APL to the J Chat forum, I feel it is my duty to 
> respond with
> > an update (not that I want to argue with your choice of  J if 
> it feels
> > comfortable for what you are doing):
> >
> >> J's portability between Windows, Mac and PDA alone sees to 
> that for me.
> >
> > OK, we don't have a "native" Mac version, but Dyalog APL does 
> run on a Mac
> > in a variety of different ways (Under Wine and various Virtual 
> Machine> frameworks). The same GUI is available on most 
> platforms, so I think that
> > your ability to produce good looking and portable user 
> interfaces using this
> > route should be no worse than using J - and could be 
> significantly better
> > depending on what you are trying to do.
> >
> >> Code written by people who didn't appreciate []ML<-3
> >
> > OK, this DOES seem like an odd reason to switch to J ;-) (for 
> those who do
> > now know, []ML<-3 puts Dyalog APL in "APL2 Compatibility Mode").
> >
> >> []AV's are devastatingly different
> >
> > True, but now that APL has "gone Unicode", []AV is just an obsolete
> > 256-element character vector which is there in order to allow 
> old code which
> > references it directly to continue working. Dyalog APL now 
> probably has the
> > most complete (and "integrated") Unicode implementation of any array
> > language. Unlike in J (last time I looked), a Finn can just type:
> >
> >      'ä'='Säppäla'
> > 0 1 0 0 1 0 0
> >
> >> Code that needs frequent execution of B[a;b;c;d;e...]<-1 
> (uses lots of
> > memory ... etc)
> >
> > These problems are now pretty much solved in Dyalog APL (SQUAD 
> indexing has
> > been added to avoid the need for execute, and indexing has 
> been rewritten to
> > be memory-efficient).
> >
> >> Also I don't have a spare couple of grand to keep up with the 
> latest>> releases of Dyalog APL and APL+Win -- but that's not 
> the key issue
> >> because I could always find a customer to buy me the products 
> I need.
> >
> > A "non-commercial" Dyalog APL will set you back £50, and if 
> you are only
> > doing a small amount of infrequent commercial work, you can 
> pick the 2%
> > royalty agreement so that you have no up-front costs.
> >
> >> No, the key issue for me is that I've written J code in Windows,
> >> including GUI code, transferred the files to the Mac, also to 
> my HP
> >> iPAQ, an easy matter because they're ASCII txt files and it's 
> just a
> >> case of moving the dongle... and the app works First Time.
> >
> > Using text files to store APL code is becoming a common 
> technique with
> > Dyalog APL too (and the system takes care of updating the 
> script files when
> > you edit code while debugging - so you can do development both 
> by editing
> > the scripts and using the system interactively).
> >
> >> I could go on and on... This was back in the last century, 
> and things may
> > have gotten better with APL since... but I doubt it's that better.
> >
> > This reminds me of one of my favorite quotes:
> >
> > http://www.youtube.com/watch?v=VgGc9kruiLQ
> >
> > Well, I don't think it was *that* bad to begin with, but I am 
> happy that
> > some of your most important complaints seem to have been 
> resolved. We've
> > certainly been busy!
> >
> >> J is going to be my tool of choice.
> >
> > I'm not trying to argue with that, just needed to set the 
> record straight
> > (as I see it ;-) regarding some of the things you state are 
> "wrong" with
> > APL.
> >
> >> BTW who's seen
> > 
> http://en.wikipedia.org/wiki/Criticism_of_the_APL_programming_language>
> > I'd better take a look at that ... :-)
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