In J, a string is represented as a _box- containing a vector of characters.
Because makes an atom of its argument, the = operation works as you'd expect.
For example:
Please excuse typos; composed on a handheld device.
-Original Message-
From: PackRat pack...@anet.com
Sender:
Though not my usual position on J development, I'd support decommissioning 13 :
.
I see its function as more appropriate to a standard library than a primitive.
For one thing, libraries are easier to change than primitives, and therefore
more amenable to user feedback.
For another, I see
Why would matrix inversion be the jewel in the crown of APL?
-Dan
On Feb 25, 2012, at 5:58 PM, Ian Clark earthspo...@gmail.com wrote:
I'd say any publicity for practical uses of (;:) is good. Even if only
because it's Alan Turing's 100th anniversary (celebrated this week by
Nature
The Wiki has a long memory: http://www.jsoftware.com/jwiki/Scripts/Fixargs .
(Fortunately for we tacit weirdos, this has never been an issue. Now, if we
changed the spelling of @ )
-Dan
-Original Message-
From: programming-boun...@jsoftware.com
...@jsoftware.com
[mailto:programming-boun...@jsoftware.com] On Behalf Of Raul Miller
Sent: Wednesday, February 22, 2012 10:08 AM
To: Programming forum
Subject: Re: [Jprogramming] Challenge 7 March Bad Mess
Or [.
--
Raul
On Wed, Feb 22, 2012 at 9:56 AM, Dan Bron j...@bron.us wrote:
The Wiki has a long
a proper linear representation. This might be a
really hard challenge because that bug has proven to be very resistant.
From: programming-boun...@jsoftware.com [programming-boun...@jsoftware.com]
on behalf of Dan Bron [j...@bron.us]
Sent
excuse typos; composed on a handheld device.
-Original Message-
From: Dan Bron j...@bron.us
Sender: programming-boun...@jsoftware.com
Date: Thu, 23 Feb 2012 04:51:03
To: J Programmingprogramming@jsoftware.com
Reply-To: Programming forum programming@jsoftware.com
Subject: Re: [Jprogramming
[mailto:programming-boun...@jsoftware.com] On Behalf Of Dan Bron
Sent: Monday, February 20, 2012 8:03 PM
To: 'Programming forum'
Subject: Re: [Jprogramming] tacit adverb
Oh, and would it be valuable if the domain were extended to nouns, in
particular literal vectors or boxed strings which represent J names
A=: 1 : '0(;@:u) :: empty'
Can be expressed tacitly as B=: 0(;@:) (:: empty) . In general, tacit
adverbs are trains of adverbial clauses, so if you want to add another, you
only need to wrap it in parens and tack it on the end.
Though your phrasing 0(;@:) is very appealing; it seems to
but quite
more difficult (as far as I can see).
From: programming-boun...@jsoftware.com [programming-boun...@jsoftware.com]
on behalf of Dan Bron [j...@bron.us]
Sent: Monday, February 20, 2012 11:02 AM
To: 'Programming forum'
Subject: Re: [Jprogramming] tacit
Oh, and would it be valuable if the domain were extended to nouns, in
particular literal vectors or boxed strings which represent J names,
potentially pro-adverbs or pro-conjunctions?
-Dan
-Original Message-
From: Dan Bron [mailto:j...@bron.us]
Sent: Monday, February 20, 2012 8:01 PM
Because in many contexts, a scalar is more convenient than a 1-element vector,
I make a habit of tacking on a {. as in {.u`'' .
-Dan
On Feb 18, 2012, at 9:32 AM, Raul Miller rauldmil...@gmail.com wrote:
I would use u`''
avg 1 :'u`'
+---+
|avg|
+---+
avg
|value error:
was also
generating a 1 element vector, so I decided that a 1-element vector
was an appropriate result.
--
Raul
On Sat, Feb 18, 2012 at 9:48 AM, Dan Bron j...@bron.us wrote:
Because in many contexts, a scalar is more convenient than a 1-element
vector, I make a habit of tacking
with primitives that handle gerunds, we are getting into undocumented
territory.
--
Raul
On Sat, Feb 18, 2012 at 11:18 AM, Dan Bron j...@bron.us wrote:
That makes sense.
My personal impression was that the original vector-ness was an
(unintentional) side-effect of the method used to remove
display in function tables
I think Dan has it right. A gerund is an atomic representation of a
verb. Could be a scalar (I use them that way a lot).
Henry Rich
On 2/18/2012 1:10 PM, Dan Bron wrote:
I'm not sure gerunds are defined anywhere.
But if they were, the phrasing might be arrays
.htm
You might argue that the definition is informal -- like most of J --
but I do not think it's fair to say that they are not defined
anywhere.
--
Raul
On Sat, Feb 18, 2012 at 1:10 PM, Dan Bron j...@bron.us wrote:
I'm not sure gerunds are defined anywhere.
But if they were, the phrasing
for gerund:
http://www.jsoftware.com/docs/help701/learning/14.htm
You might argue that the definition is informal -- like most of J --
but I do not think it's fair to say that they are not defined
anywhere.
--
Raul
On Sat, Feb 18, 2012 at 1:10 PM, Dan Bron j...@bron.us wrote:
I'm not sure
Neat application!
What behavior of 5!:5 do you use here, that is undocumented? The question of
whether the behavior you observed in `:6 here, hinges on the definition of
gerund, and the fact that you can do just this is one reason why I defined it
as I did. Moreover, this behavior is
I haven't been following this thread, but instead of C routines, could you make
use of the several file-handle related foreigns in the 1!: family?
http://www.jsoftware.com/help/dictionary/dx001.htm
1!:20 y File Numbers and Names. A 2-column table of the open file
numbers and
Linda wrote:
Design a function with no restrictions
on style or specific functions.
I'm glad the constraints on style and presentation were lifted.
Linda wrote:
PLEASE DO NOT RESPOND UNTIL 2/22/2012
Raul responded:
Please send again when we
can respond -- I will read it then.
I
Marc Simpson wrote:
One thing though-the original problem stated that:
Each row is a successive scramble of the character
string above it with one added symbol
Ah, I must've glossed over this part. Thanks for the tip. Here's another
take:
**SPOILER AFTER 15 BLANK LINES**
**SPOILER AFTER 15 BLANK LINES**
I wrote:
I've always liked i..- though. It's cute.
I guess I should explicitly point out that an alternative to i..-@# is
-@#\. which is shorter and rhymes with the original expression, but loses
the cuteness of . .
-Dan
Linda wrote:
Cap
|domain error
Yes, as I noted in my original message, there is a bug in the display family
(5!:) that prevents the definition of Cap from being displayed. It boils
down to this:
((:0)`)
|domain error
Which has been known for a while. If this clause
: [Jprogramming] Another early morning exercise
What is the definition of Cap being used here? If Cap is defined as
Cap=:[:
it works fine.
5!:5'Cap'
[:
1 2([: *: +)3 4
16 36
1 2(Cap *: +)3 4
16 36
On Sun, Feb 12, 2012 at 10:30 AM, Dan Bron j...@bron.us wrote:
Linda wrote:
Cap
Raul wrote:
My impression was that she was looking for something
to transform ([: U V)V to use @ instead of [:
Ah, ok, hence UnCap. This wouldn't be difficult to do; most of the tools
needed were developed to produce Cap, and are available in [1].
But, reading your comments in another
Unlike C, where \ introduces an escape sequence within string liberals, in J,
the only special character in a literal is ' (single quote).
So, to embed quotes in strings, double them up: a. i. '(`''3' . Of course,
recursively embedded quotes need quadrupling, octupling, etc (eg 'he said
and the trouble is with
parsing them using ;: (instead of evaluating them in the immex session), then
you could try something along the lines of (#~ 2 * = ]) y (i.e. double
singleton quotes).
-Dan
Please excuse typos; composed on a handheld device.
-Original Message-
From: Dan
Linda wrote:
I was trying to find a situation where you have to
use @ instead ( of [: ).
I think Raul pointed out that u@v = ([: u v)v so that you never /have/ to
use @ . You can mechanically convert from one formulation to the other. So I
figured I'd provide you a tool to do just
Linda, Boyko's not the first to express this sentiment to you. Don't you
wonder what the mysterious appeal of @ is? If so, maybe a more rewarding (and
commensurately challenging) exercise for you this morning is:
translate from expressions without @ to ones with it
For example, you
Hmm. I could do a basic intro to J course at one of the NYC JUGs. If we
broadcast record it, we could then post it on youtube.
The question is: who is the audience? What do they already know about J?
What do they want to know?
-Dan
-Original Message-
From:
I asked:
Why should we avoid @ ?
Linda responded:
It encourages and fosters thinking
from applying functions from left to
right.
Raul followed-up:
*: -: 8
*:@-: 8
I am not seeing a big left-to-right vs. right-to-left difference, here.
I'm with Raul. My sense is the aversion
Linda Alvord wrote:
please do not use @
I know this has been asked before, and I may have missed the answer (forgive
me if so).
Why should we avoid @ ? That's like posting a Unix shell-scripting
challenge, and saying avoid | (use file redirects instead).
-Dan
/./ matrix
-Dan
Please excuse typos; composed on a handheld device.
-Original Message-
From: Ben Gorte - LR b.g.h.go...@tudelft.nl
Sender: programming-boun...@jsoftware.com
Date: Tue, 10 Jan 2012 14:40:41
To: Programming forum (programming@jsoftware.com)programming@jsoftware.com
J has copy-by-value semantics. By default, all outputs occupy separate
memory spaces from their corresponding inputs. It's a safety net, which,
given that a lot of J programming is exploration, is very nice to have. Put
another way, this is one of the design decisions that contributes to J's
, Jan 6, 2012 at 10:39 AM, Dan Bron j...@bron.us wrote:
J has copy-by-value semantics. By default, all outputs occupy separate
memory spaces from their corresponding inputs. It's a safety net, which,
given that a lot of J programming is exploration, is very nice to have.
Put
another way
Two resources occur to me. The first is probably closest to what you're
asking for:
http://www.jsoftware.com/jwiki/APL2JPhraseBook
credit to Ian Clark on that one. The second is a horse of a different
color:
http://rosettacode.org/wiki/J
Much like the Rosetta Stone helped
Thank you for the generous present! I notice it has my name in the lead :)
I'll review it soon and send any notes I may have.
Have a happy and prosperous new year!
-Dan
-Original Message-
From: programming-boun...@jsoftware.com
[mailto:programming-boun...@jsoftware.com] On Behalf Of
Oops, sorry guys! I hit reply to the wrong message; this was supposed to go
to R.E. off-line.
But, of course, a happy and prosperous new year to you all, as well!
-Dan
-Original Message-
From: programming-boun...@jsoftware.com
[mailto:programming-boun...@jsoftware.com] On Behalf Of Dan
The issue is that } is an adverb.
So, even though V0 } V1 looks like a verb train, it's actually a hook, parsed
as (V0}) V1 , which doesn't do what you want.
You're looking for (OLD=)`(,:NEW) } . This is one of my very favorite J
phrases.
-Dan
Please excuse typos; composed on a handheld
PM, Dan Bron j...@bron.us wrote:
Marshall wrote:
(negative MSB) version is mathematically more well-founded
I am personally not qualified to assess the mathematical virtues of the
different formulations. And I see (more than) enough mathematical
horsepower on these Forums to be confident
It might be that in retrospect, an LSB-approach to #: would have been more
in the spirit of J. It would have allowed us to give the monad #: its
proper rank of zero, for example.
.. that said, it works against the grain of most important information
first, as expressed in our usual left-to-right
I think we need use-cases for #: with negative arguments.
I've probably hit some, over the years, but I can't recall any at the moment.
Anyone else?
-Dan
-Original Message-
From: programming-boun...@jsoftware.com
[mailto:programming-boun...@jsoftware.com] On Behalf Of Raul Miller
Maybe we should explore a different track. Forget all about the history of
computing hardware, and the advantages of one representation over another
when designing circuits. In purely mathematical terms, what are the decimal
digits of the base-10 number -123 ?
Working backwards:
_123
1 1
0 1 0 0
0 1 0 1
#. base i:5
_5 _4 _3 _2 _1 0 1 2 3 4 5
Marshall
On Mon, Dec 12, 2011 at 2:09 PM, Dan Bron j...@bron.us wrote:
Maybe we should explore a different track. Forget all about the history
of
computing hardware, and the advantages of one representation over another
#: should have been designed
And (* * #:@:|) achieves this result.
#. (* * #:@:|) i: 3
_3 _2 _1 0 1 2 3
That's probably good enough for now.
--
Raul
On Mon, Dec 12, 2011 at 4:34 PM, Dan Bron j...@bron.us wrote:
I don't think there's a violation of a uniqueness constraint.
Consider
Marshall wrote:
(negative MSB) version is mathematically more well-founded
I am personally not qualified to assess the mathematical virtues of the
different formulations. And I see (more than) enough mathematical
horsepower on these Forums to be confident that a sensible conclusion will
be
I can't speak for Raul, obviously, but:
- J is a (programming) language
- It is used to express (and sometimes execute) ideas, using a
vocabulary
So, asking where did you get this? of the sentence (,+/i./ 2{.1 1,~$y)
u key ,/y is not very different than asking it of the
~:/\ ]={. ).
Thanks for jumping in when you are needed.
R.E. Boss
-Oorspronkelijk bericht-
Van: programming-boun...@jsoftware.com
[mailto:programming-boun...@jsoftware.com] Namens Dan Bron
Verzonden: vrijdag 25 november 2011 4:43
Aan: 'Programming forum'
Onderwerp: Re: [Jprogramming
This looks similar to boxing a recursively nested parenthesized expression
(or XML, or whatever). So, we can use recursion:
foo =: ] `(@$:);.1~ 1 , 2 ~:/\ ]={.
foo 1 1 2 2 3 3 4 2 3 4 4 1 2 2 2 1
+---+---+-+---+-+
|1
Raul Miller wrote:
foo=: ^:{./.~ [: +/\ 0,2 ~:/\ ]
REB asked for a foo such that:
foo 1 1 2 2 3 3 4 2 3 4 4 1 2 2 2 1
+---+---+-+---+-+
|1 1|+---+-+-+-+|1|+-+|1|
| ||2 2|+---+---+|2|+-+-+|| ||2 2 2|| |
Yes, you want x=._ (infinity). Thus, f^:(_) y or you can use the convenient
shorthand form, f^:a: y .
-Dan
On Nov 20, 2011, at 5:36 AM, David Vaughan purpleblue...@googlemail.com wrote:
If I'm doing f^:(x) y, can I write an expression so that f is repeatedly
applied to y until the result
How about a more difficult challenge? It's related. No embargo period on this
one.
Write a 13 : '' for Simple J. In particular, write an adverb which, given
an anonymous tacit verb as an argument, derives a functionally identical verb
(in terms of I/O), but all instances of f@:g are
Don't try to fit J into any pre-existing mental models you may have.
Create a clean, empty category for it in your mind, and enter J as the first
member of the population.
You can call the category array-oriented languages, if you like. Other
potential members are APL and K.
-Dan
PS:
0
Please excuse typos; composed on a handheld device.
-Original Message-
From: Henry Rich henryhr...@nc.rr.com
Sender: programming-boun...@jsoftware.com
Date: Sun, 30 Oct 2011 09:18:46
To: Programming forumprogramming@jsoftware.com
Reply-To: Programming forum programming@jsoftware.com
Please excuse typos; composed on a handheld device.
-Original Message-
From: Linda Alvord lindaalv...@verizon.net
Sender: programming-boun...@jsoftware.com
Date: Sat, 29 Oct 2011 12:05:37
To: 'Programming forum'programming@jsoftware.com
Reply-To: Programming forum
Composition vs application?
Please excuse typos; composed on a handheld device.
-Original Message-
From: Roger Hui rogerhui.can...@gmail.com
Sender: programming-boun...@jsoftware.com
Date: Fri, 21 Oct 2011 15:05:17
To: Programming forumprogramming@jsoftware.com
Reply-To: Programming
I haven't been following the Forums closely, but there has been traffic
recently regarding invisible Unicode whitespace chars giving J a hard time
(spelling errors). Browsers introduce non-breaking spaces or something during
copy/paste. Think Raul or Roger posted some tool to identify the
Raul wrote:
{.^:(#@$) i.-5 4 3 2
119
{., i.-5 4 3 2
119
Henry said:
Point of nomenclature: every noun has a shape.
All shapes are lists.
The shape of an atom is an empty list.
So Henry's given us a big hint here:
'' ($,) i.-5 4 3 2
119
And, if you
Anything you can write in the browser window (IJX) or an explicit verb, or
anywhere else in J, can be written tacitly. The only restriction on tacit
code is it is stateless (no use of =: =. ). So, yes, you can use e.
tacitly.
The issue you're having is due to [: . That verb (it is a verb,
not sure what d is.
([: d e.~ ]) 2
Linda
-Original Message-
From: programming-boun...@jsoftware.com
[mailto:programming-boun...@jsoftware.com] On Behalf Of Dan Bron
Sent: Thursday, October 13, 2011 10:40 AM
To: 'Programming forum'
Subject: Re: [Jprogramming] Remove part of rank-2 array
Couple of points. You can detect name changes with 4!:5 [1] and the names
returned will be fully qualified, meaning you'll be able to identify what
locale the changed name is in. I'm not in front of an interpreter right now,
but it's something along the lines of:
4!:5.i.2 NB. Top of
his panic
imp art
the rapist
-Original Message-
From: programming-boun...@jsoftware.com
[mailto:programming-boun...@jsoftware.com] On Behalf Of Raul Miller
Sent: Thursday, September 29, 2011 6:13 AM
To: Programming forum
Subject: Re: [Jprogramming] Permutations
Cool. Are general J papers welcome? That is, papers on the subject of J,
rather than applications of J to science?
-Dan
-Original Message-
From: programming-boun...@jsoftware.com
[mailto:programming-boun...@jsoftware.com] On Behalf Of mikel paternain
Sent: Tuesday, September 27, 2011
IMO, this piece of code is getting more attention than it merits. It's a
simple utility, written long ago, and mostly used interactively in the REPL
while debugging or just exploring (i.e. in throwaway contexts).
If you want different behavior than nl et al provide, it's easy enough to
write
If speed is a big concern, then I imagine (haven't tested) that : would
be faster than 10#.^:_1 .
I used to have an intellectual distaste for choosing : to get the digits of
the number (because I'm dealing with numbers, not strings, right?) but
someone recently pointed out that to even say
Conjunctions: no (at least officially, though I have my suspicions)
Adverbs, yes: www.jsoftware.com/pipermail/programming/2010-November/021172.html
Relevant documentation is II.E (parse table) and II.F (trains, including the
adverb train rule).
-Dan
Please excuse typos; composed on a
_ . boxed
Please excuse typos; composed on a handheld device.
-Original Message-
From: james wafula jbukos...@yahoo.com
Sender: programming-boun...@jsoftware.com
Date: Tue, 23 Aug 2011 06:07:58
To: programming@jsoftware.comprogramming@jsoftware.com
Reply-To: Programming forum
Just as an example, here's how indexOf in J works:
'ABCDEFGHIJKLMNABC' i. 'ADKz'
0 3 10 17
A few notes:
- The universe of all things (i.e. the source) is on the left,
the target is on the right
- You can look up multiple things simultaneously
I think the more puzzling behavior here isn't that ?. is different from ? but
that ?. is giving a manifestly incorrect result wrt its definition. Whatever
rank ?. is, each element of its result should be strictly less than the
corresponding atom of its argument. Also an output of _ is just
forumprogramming@jsoftware.com
Reply-To: Programming forum programming@jsoftware.com
Subject: Re: [Jprogramming] Subject: monadic rank of roll and deal
_ was not an output, it was part of the rank.
--
Raul
On Mon, Aug 8, 2011 at 10:48 AM, Dan Bron j...@bron.us wrote:
I think the more puzzling behavior here
Just a typo. You need an assingment like this
compress =: 4 : 0
)
Please excuse typos; composed on a handheld device.
-Original Message-
From: nykkyo Kane nyk...@ymail.com
Sender: programming-boun...@jsoftware.com
Date: Sun, 7 Aug 2011 19:56:33
To:
The J Forum is the most useful part of the documentation. J without the
Forum would be like J without the immediate execution window. It would be
like trying to code C while sober.
-Dan
-Original Message-
From: programming-boun...@jsoftware.com
Verbal amend is under-documented and rarely used, due to the property you've
discovered.
In fact, verbal amend is only ever used when that property is desired.
Otherwise, one would use the noun or gerundial form.
The property is that in x f} y the verb f addresses indices into the
The sum of the digits 0-9 is 45 and 4+5 is 9 so any number containing the
digits 0-9 exactly once is going to be divisible by 9, and hence will not be
prime.
You're going to have to look for pandigital numbers containing repeated
digits, that is N 9876543210 . So you can skip the permutation
Please excuse typos; composed on a handheld device.
-Original Message-
From: david alis david.a...@gmail.com
Sender: programming-boun...@jsoftware.com
Date: Sun, 3 Jul 2011 15:34:18
To: Programming forumprogramming@jsoftware.com
Reply-To: Programming forum programming@jsoftware.com
I haven't read the responses to this yet but I'm sure someone has explained the
difference.
In short, @ is an assembly line, items being passed between workers one at a
time, and @: is a hopper, all items being passed between workers in a batch.
Quick'n easy ruke of thumb: always use @: except
Why is the description restricted to one word?
Why are haikus restricted to 17 syllables?
Anyway, the contemporary version of the elevator pitch is a tweet.
Can you capture J in 140 characters, or less?
-Dan
-Original Message-
From: programming-boun...@jsoftware.com
To: Programming forum
Subject: Re: [Jprogramming] One word description of J
jtweet=: 0 : 0
J is a programming language that works with
arrays, verbs, and adverbs. For example,
+/x computes the sum of array x and /:~x sorts it.
)
# jtweet
138
- Original Message -
From: Dan Bron j
Since this is a fairly industry-specific format, and the verbs consequently
are use-case-specific, it might be cleaner (and easier) to create a JAL
addon for these related surveying utilities.
-Dan
-Original Message-
From: programming-boun...@jsoftware.com
assignments to mapped files
Thanks, Dan.
Works nicely, and is slightly faster than: $ $ ,
Ian
On Sat, May 28, 2011 at 12:52 AM, Dan Bron j...@bron.us wrote:
Ian asked:
Can you think of a low-overhead verb which
will force J to allocate sav its own separate
space in memory?
Try
What's a clear, short verb to select random items in a weighted fashion?
Something like ? only:
#0 Ranks 1 0 1
#1 y=.vector of weights (proportional to their total)
#2 x=.number of trials
#3 the monad is the dyad with a fixed left arg of 1, i.e. 1$: :
( ... )
?@$ 0
2 3 2 3 2 2 3 3 3 1 3 2 1 3 3 3 1 0 1 2
- Original Message -
From: Dan Bron j...@bron.us
Date: Friday, May 27, 2011 9:39
Subject: [Jprogramming] Weighted random selection
To: 'Programming forum' programming@jsoftware.com
What's a clear, short verb to select random items
500276
The coin seems pretty fair to me.
- Original Message -
From: Dan Bron j...@bron.us
Date: Friday, May 27, 2011 10:08
Subject: Re: [Jprogramming] Weighted random selection
To: J Programming programming@jsoftware.com
At first blush, that seems like it would favor higher indices
Devon wrote:
We must be on the same wavelength lately
I came up with pickFrom=: ] {~ [ ?@$ [: # ]
Devon, we're on the same wavelength but in a different phase. Your code
picks a random item from a list (and could leverage a hook if you like:
pickFrom=: ] {~ (?@$ #) ).
My code does
Brian wrote:
Does the filter (%+./) solve the big and
fractional weights issue?
It definitely solves the fractional weights issue, by normalizing everything
to integers. I'll have to remember that, that's a neat tool.
However, it doesn't solve the big weights issue, as e.g. one of the
Which is to say: exactly as much as your machine can handle (note the formula
below also defines the limits of memory pointers on modern architectures).
Which should also tell you that the max number of items depends on the size (in
memory) of 1 item. The smallest J item is one byte (a
. Re: Sorting (Pablo Landherr)
5. Re: Sorting (bill lam)
6. Re: Sorting (R.E. Boss)
7. Re: Sorting (bill lam)
8. Re: J arrays (Dan Bron)
9. Re: Sorting (Devon McCormick)
--
Message: 1
Date: Wed, 25 May 2011 05:23:23
You're using the monad . , Do, which executes valid J sentences (i.e. just
like the things you can type into the IJX window). 1e+2 is not a valid J
sentence.
What you want is the dyad . , Numbers, which provides the leeway you
quoted:
_ . '1e+2'
100
-Dan
-Original
The links posted in this thread (excised) are pretty clearly spam and very
likely exploit sites. Can the list moderators please remove Denis Samson?
(I suspect Denis himself is blameless but it looks like his email account
has been compromised.)
-Dan
-Original Message-
From:
.
R.E. Boss
-Oorspronkelijk bericht-
Van: programming-boun...@jsoftware.com [mailto:programming-
boun...@jsoftware.com] Namens Dan Bron
Verzonden: vrijdag 6 mei 2011 14:49
Aan: 'Programming forum'
Onderwerp: Re: [Jprogramming] (no subject)
The links posted in this thread (excised
Steven Taylor asked:
btw: why is this useful?
R.E. Boss responded:
why is this useful?
Like poetry is useful.
An applaudable analogy. In fact, I applaud.
-Dan
PS: The J phrase (poem), too.
Please excuse typos; composed on a handheld device.
-Original Message-
From: R.E. Boss
foo =: @(0,[) C. i.@]
(Untested)
-Dan
Please excuse typos; composed on a handheld device.
-Original Message-
From: Ian Clark earthspo...@gmail.com
Sender: programming-boun...@jsoftware.com
Date: Fri, 29 Apr 2011 13:03:55
To: Programming forumprogramming@jsoftware.com
Reply-To:
Sorry, I didn't read your output carefully so I mistinterpreted your question
(thought you wanted to swap posn 0 with posn x).
-Dan
Please excuse typos; composed on a handheld device.
-Original Message-
From: Dan Bron j...@bron.us
Date: Fri, 29 Apr 2011 12:07:53
To: J
Cool, elegant approach. I think we could trim off the merge using A., but I do
not have an interpreter in front of me, and Oleg's brinkster interpreter has
gone away :(
Anyway if you apply monad A. to Henry's output, or the output of the original
foo, you'll find out what the LHA to dyad A.
Apply the monad C. to the output of foo to discover the LHA required by the
dyad C. to permute i. to foo .
Similarly for A.
-Dan
Please excuse typos; composed on a handheld device.
-Original Message-
From: Ian Clark earthspo...@gmail.com
Sender: programming-boun...@jsoftware.com
Depends on which argument is data (calculated, changes frequently) and which
is control (fixed, or changes infrequently wrt the data).
In other words, if you wanted to make a reusable verb, which is more likely in
your context:
deal =: 3?
or
deal =: ?10
?
If the former (which
Nobody optimizes any more; premature abstraction is the new evil -
@stuartsierra
Stuart Sierra http://twitter.com/#!/stuartsierra/status/34967735423205376
-Dan
-Original Message-
From: programming-boun...@jsoftware.com
[mailto:programming-boun...@jsoftware.com] On Behalf Of Devon
For equal-length arguments, you can say repeats ;@:(#.) values .
For equal- or unequal-length arguments, you can say repeats ;@:(#.)
/@:(./.:@:,:$ $. ,) values .
There might be a cleaner way to force agreement in shape by filling
cylically; I'm just throwing this out there.
-Dan
The current implementation [of M.] retains
results only for arguments that are small
non-negative integer atoms.
If it helps, any argument can be turned into a small non-negative integer
with 6 s: s:@:(3!:1)@: . If you want an M.-like adverb that applies this
transformation first,
-Original Message-
From: Raul Miller [mailto:rauldmil...@gmail.com]
Sent: Monday, February 28, 2011 12:34 PM
To: Programming forum
Cc: Dan Bron; David Ward Lambert
Subject: Re: [Jprogramming] timing doesn't scale to large problem size.
On Mon, Feb 28, 2011 at 11:48 AM, Dan Bron j
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