A fork can be done in a friendly way or a hostile way. A friendly fork
would provide something (perhaps some niche feature) that Jsoftware
themselves cannot, and would actively help Jsoftware benefit from the added
use (perhaps niche publicity, perhaps core bug fixes).
There are a million ways to
I think you should post THAT review on Lulu -- it persuaded me.
On Sun, Feb 28, 2016 at 6:38 PM Ian Clark wrote:
> Thanks for bringing this up-to-date, Cliff. Eager for Part 2.
>
> This has long been on my bucket-list for serious study, of the sort I
> last gave to "At Play With J" by J doyen Ge
That's a really good idea -- you should check out and meld this with the
prior work in Stern-Brocot trees. They're basically ordinal fractions which
allow one to iterate in an orderly manner through all the ranges of
rationals within a given range.
http://arxiv.org/abs/cs/0401014 (uses the term "F
bill lam wrote:
> Has the n-sphere become concave in higher dimension?
>
Think of it this way: you're nesting a sphere inside a box, so the volume
"wasted" is simply the corners of the box. But every time you increase the
number of dimensions, you vastly increase the number of corners the box ha
Sure you can compare; the difference is how hard it is to find the sphere
when all you have is a bounding box and an RNG.
On Fri, Aug 18, 2017 at 7:16 AM Xiao-Yong Jin wrote:
> You can't compare quantities with different dimensions.
> It's meaningless, like saying the water in your cup in cm^3 i
g 18, 2017 at 1:05 PM, Xiao-Yong Jin
> wrote:
>
> > That's a dimensionless ratio.
> >
> > > On Aug 18, 2017, at 11:19 AM, William Tanksley, Jr <
> > wtanksle...@gmail.com> wrote:
> > >
> > > Sure you can compare; the difference is how hard it is
It's available for Android at least.
On Thu, Sep 28, 2017 at 12:46 PM Eric Iverson
wrote:
> zmq is a portable library and runs on many platforms. In particular it runs
> on windows/linux/osx/rpi. Probably not on mobile devices, but I am not
> sure.
>
> On Thu, Sep 28, 2017 at 1:30 PM, Björn Helg
Irrational numbers cannot be represented by floats, rationals, or integers.
You'd have to make a special type to represent irrationals, and of course
it would only represent as many of them as you choose to assign values to
(for example, your type might represent a floating point number times the
s
You could do this with rational numbers, since whether or not they
terminate IS an interesting puzzle. Of course, you have to specify a
"decimal" base -- 1/3 doesn't terminate base 10, but does terminate base 60.
On Wed, Jun 13, 2018 at 12:26 PM Raul Miller wrote:
> Floating point numbers implic
digits of decimal (base 10 (base 10 (base 10
> (... precision might be a sweet spot.
>
> Thanks,
>
> --
> Raul
>
> On Wed, Jun 13, 2018 at 3:34 PM William Tanksley, Jr
> wrote:
> >
> > You could do this with rational numbers, since whether or not they
&
I have no idea why you're saying that. Irrationals don't have denominators;
they cannot be written as fractions. And no floating point numbers are
irrationals.
On Thu, Jun 14, 2018 at 12:18 AM 'Bo Jacoby' via Programming <
programm...@jsoftware.com> wrote:
> If a floating point number (a) , is ir
I use the MessageEase keyboard (free), which gives me instant access
to most symbols, letters, and digits without shifting, although at the
cost of a very nonstandard layout. (You'll want to use the tutor game
to bring you up to speed.)
On Tue, Feb 11, 2014 at 2:27 PM, Devon McCormick wrote:
> Th
I use the same phone. You can turn the keyboard on and off by pulling
down the notification bar while you're in a text field, and tapping
the "Switch Keyboard" notification. It's not a perfect solution,
though, unless your J keyboard is good enough for routine use. I
personally use MessageEase, whi
Alex Giannakopoulos wrote:
> Skip, I am glad you mentioned this. I've been suffering too. (It's not
> just Samsung, BTW, all Android devices have some sort of smart keyboard
> that interferes, even if they (the keyboards) are not always the same.
The current solution is to install a keyboard th
greg heil wrote:
> MessageEase is great! Thanks Wm!
Cool, I use it for everything. (The ME tutor "game" helps a LOT.)
Another idea, although more expensive, is "Grafitti" -- the glyph
recognition system.
> There seems to be no way of making a selection (nor change the selection:)
> nor a way t
The problem is that shoveling wide pointers has a cost; 64-bit builds
have measurable costs even now.
It's not _always_ wise to solve tomorrow's problems today -- tomorrow
often has its own technologies.
On Thu, Jun 12, 2014 at 1:50 PM, Don Guinn wrote:
> True, except that is a real memory limit
Skip Cave wrote:
> I can enter J immediate execution commands such as 3 + 3 4 5, or i.5 and
> get the correct result on my phone. Very nice!
Agree!
> how to get
> the improved keyboard talked about on the forum,
I can help with this one. Go into the system Settings (not J's
settings -- the Andr
Brian Schott wrote:
> Now I want to know if any gmail users know how to use the keyboard and
> not the mouse to delete a message, not a conversation. I used to be
I don't see how to delete a message, but I have part of the puzzle --
"p/n" work to highlight a specific message; if the one you want
Don & Cathy Kelly wrote:
> array oriented languages. Look at the power of a simple +/ vs the Python,
> Fortran, Basic, C approach? Try out the 1 o. o.0.1*i.10 equivalent in
> Python without writing a loop.
I don't think that's the big advantage... Python's code for that isn't
much worse (I don'
Boyko Bantchev wrote:
> Traditional algebraic notation is very good for what it has been
> designed, and much easier to learn for kids than parsing J, let alone
> understanding the underlying computational model.
I've done some classroom teaching and small-group tutoring, and it is
not my experie
Boyko Bantchev wrote:
> William Tanksley wrote:
>> "Let me know -- where did you teach that gave you the idea that people
>> find traditional notation easy?"
> I did, and I am teaching to both university students and school students.
> I'll add that they are not the crowd that would fail at algeb
David Ward Lambert wrote:
>NB. Bring on the heavy weights! Find one root.
>NB. The other could be found by polynomial division
>NB. which I'm quite sure is demonstrated in the j phrases.
>load'~addons/math/misc/amoeba.ijs'
YES! This is a _cool_ way to find a root. (He didn't ask
Long-pressing works for Android less than version 4.0; for that version you
use the notification that shows up whenever the keyboard is up (drag down
the top bar).
-Wm
Fraser Jackson wrote:
> The help text states that 'long-pressing on the console screen will bring
> up a menu with the item "
The BWT by definition HAS to pass extra data to track the beginning of
the string.
Here's a similar transform that doesn't:
http://arxiv.org/abs/1201.3077
No, I don't understand it at all, sorry.
-Wm
On Sat, Feb 2, 2013 at 7:08 PM, Raul Miller wrote:
> Here's a slightly flawed implementation
I very much enjoy J for Android, and look forward to hearing more
about the alpha as it progresses.
I don't want to install the alpha, since I'm still learning the
language, but I will as soon as someone can confirm that it works OK;
I'd like to help this along, since it looks like this will event
That really is magnificent -- and I speak as someone who stopped trying to
learn APL (before J was easily available) because I found the character set
unapproachable. I could easily see myself switching to that overlay for
normal coding and reading.
I'd like to see this developed into a coherent s
Devon McCormick wrote:
> This is nice but avoids the hard parts of the problem.
Sure, it's a proof of concept rather than an implementation. It serves
a different purpose -- rather than solving the entire problem, it
solves the problem of people doubting whether it would really look and
feel OK.
John Baker wrote:
> I'd also
> ignore keyboard issues. Keyboards are already virtual on phones and tablets
> and before long QWERTYUIOP keyboards will join card punches in the ever
> expanding warehouse of obsolete computer memorabilia.
There are by definition no keyboard issues for a J standard
PMA wrote:
> Yes, if the relatedness within each primitive set gets lost,
> won't a need for 3-to-6 times the number of J primitives
> virtually cancel any one-token-per-command advantage?
No, it won't cancel "any" (by which I mean "all") of the advantage.
But yes, it will lose SOME. It's a trade
Skip Cave wrote:
> William,
> You are overlooking the option of writing the single-character glyphs on a
> touchscreen, using handwriting recognition.
That sounds like a pleasant way to augment a keyboard-based entry if
we decide to go with glyphs that don't resemble the underlying
characters --
Raul Miller wrote:
> Anyways, that looks interesting (and similar to the paper William
> Tanksley, Jr. referred to - though the paper you refer to here was
> published 3 years earlier).
That is indeed interesting and similar. The difference is also interesting.
The baseline BWT sor
PMA wrote:
> Ok, saying "any" was my bad.
Not at all, you were perfectly clear in context. I just found myself
unable to echo you without the same context, so I had to provide
additional information.
> But I want to convey that
> for me this relatedness -- the primitive set as a family --
> is m
neville holmes wrote:
> Provide an option whereby J. primitives can be displayed
> as the base J character but in (say) red, and J: primitives
> can be displayed in (say) green.
Humans don't process color with the same circuits that process text;
so where color reinforces what the text says it's
Alan Stebbens wrote:
> It seems reasonable that the people motivated to have a non-ASCII input
> and presentation mode for J should develop a working prototype, or work
> with someone who has the skills to do it, so that all of these
> discussions on an "ideal symbols for J" can be evaluated throu
William Tanksley, Jr wrote:
>> PS: Even if this discussion leads to a good alternative input method
>> implementation, there is still a ton of work involved in transcribing
>> (or rerendering) all the existing J symbols (digraphs and trigraphs)
>> into the new symbols (wh
Tracy Harms wrote:
> Making the dots bigger might help a lot. Here's an idea that might be
> relatively simple: have a J tokenizer active during typing, and every
> inflected graphic primary gets changed so that the dots are both enlarged
> and overlaid on the graphic. By "overlaid" I mean the res
Ian Clark wrote:
> William Tanksley, Jr wrote:
>> Humans don't process color with the same circuits that process text
> Doesn't the Stroop Effect
> http://en.wikipedia.org/wiki/Stroop_effect suggest they do?
> (Tightly-linked circuits, at least.)
"Circuit" i
Skip Cave wrote:
> 1. The small dots used for modifying the base ASCII characters in J are
> hard to read, and can cause confusion. Making the characters bold can help,
> but only on a computer. When writing J on paper or on a blackboard, the
> small dots still often get lost in the mix. Having to
Skip Cave wrote:
> Raul,
> Who said that ASCII English was ideal?
I do. I know, I like the idea of optionally displaying glyphs -- the
proof-of-concept was convincing. But ASCII is a _fundamental_ of
computing right now -- no matter what we might have 5 years later,
it's what we have now.
> Here
Henry Rich wrote:
> You would also have agonize over the fact that in J,
>0 * _
> 0
> which is probably not what BLAS does.
In most cases it actually IS what BLAS does -- but I do agree that
agonizing is necessary. Careful unit testing is needed.
Here's an instructive example of agonizing:
h
Here's a little discussion on how to get BLAS up and running,
including the author's recommendation of open-source choice.
http://greendotblade3.cs.nyu.edu/torch/install/blas.html
-Wm
--
For information about J forums see http://w
greg heil wrote:
> 2.5 is not even an integer, how could it be a prime?
The confusion for me is probably the same as for Raul. You are making
statements like "the hypothesis is true for all numbers tested except
2 and 3." This is confusing to both Raul and myself, because the
statement of the hyp
greg heil wrote:
> Marc
>The '>' was a discovery of mine,
>a mail user agent (MUA) sees a line beginning with > as not needing its
>services as a formatter.
I think it was a great discovery, but could you please use it only
when it's actually intended? It's _really_ hard to reply to a post
where
greg heil wrote:
>i do try not to use one on "short" lines.
Yes, that would be slightly annoying. It's only extremely annoying
when it's used on long lines -- it blocks the reply editor from being
able to properly mark your text as being a reply.
It makes a lot of sense to use it on code. I don'
Out of memory errors are notoriously hard to debug; if you need to run this
program on any different data than what you're using now I'd take up the
offer to come up with an alternate approach.
By the way, it's common for different oses to display different behavior
under pressure. Windows fails ea
Is it possible to do these plots using only algebraic functions -- for
example, using 1/x and then a rotation to plot the hyperbolae? I know
of an algebraic parameterization for the unit circle, but I'm not sure
about the ellipse.
-Wm
On Mon, Sep 16, 2013 at 3:40 PM, km wrote:
> Summary of resu
Bo Jacoby wrote:
> One benefit of using complex numbers is that you may forget about
> trigonometry.
>load'plot'
>circle=._1^n=.(%~i:)60
>ellipse=.(circle*-.a)+(+circle)*a=.0.8
>hyperbola=.-:((+%)j.(-%))^n
>plot circle,ellipse,:hyperbola
Thanks, Bo; that's what I was thinking
I'm clueless -- how would you implement one of the more formally
correct solutions (Newton's, Babylonian, exhaustive search, or random
probing)? K did pretty well.
-Wm
On Thu, Dec 12, 2013 at 11:09 AM, Dan Bron wrote:
> There is a stack exchange dedicated to code golfing,
> http://codegolf.stac
A friend of mine wrote the following paper describing his attempt to
characterize the differences between a few different styles of
implementing the same code in J a few different ways -- explicit,
implicit, and a few variations. He also baselined against a Forth
implementation.
I found his writeu
Dan Bron wrote:
> We often say the APL family of languages allow us to use language as a tool
> of thought. How does this play out in practice? Do we approach reading J
> programs differently from those written in other languages? If so, how?
I think this is a fantastic question.
I completely
Raul Miller wrote:
> I'll counter your suggestion that it's easier to write unreadable code
> in APL derivatives with an observation that looks to me like a social
> issue rather than anything intrinsic in the language.
Fascinating and very plausible. But I wasn't intending to talk about
ease of
Does J provide rational trig functions? If not, you'll want to check
out N.J. Wildberger's rational trigonometry, based on "quadrance" (an
unsquare-rooted distance) and "spread" (like a relative slope of
quadrances). That way your rational numbers will stay rational until
it's time to convert them
u can avoid using angles entirely and use mechanisms based
> on cross product for contexts that demand "sine" and dot product for
> cosine...
>
> (Not always, though - especially if you're working through someone
> else's math notes which were explicitly about angles.)
&g
Ian Clark wrote:
> But why should I feel obliged to carry on using lossy methods when I've
> just discovered I don't need to? Methods such as floating point arithmetic,
> plus truncation of infinite series at some arbitrary point. The fact that
> few practical measurements are made to an accuracy
Ian Clark wrote:
> accurate timing for GPS satellites. Both require significant relativistic
> corrections: not Special relativistic but General relativistic. When it's
OK, you have GOT to check out Wildberger's rational trig -- especially
his "universal hyperbolic geometry", which extends the w
1808│ │ 89r144│
> >> │0.61802575107296143│ │ 144r233│
> >> │0.61803713527851456│ │ 233r377│
> >> │0.61803278688524588│ │ 377r610│
> >> │0.61803444782168182│ │ 610r987│
> >> │0.61803381340012520│ │ 987r1597│
> >> │0.61
Raul Miller wrote:
> They can, which is disturbing.
> However, they don't have to (and they have some other advantages, also...).
They do have to (round and otherwise display non-arithmetic behavior).
All floats are actually rational numbers which follow a specific
format and truncate in specific
Marshall Lochbaum wrote:
> It's getting late, so I'll stop for now (only one line left now,
> though!). I'll pick up tomorrow, and bank on the fact that it will take
> much longer to read this than it did to write it.
It's worth reading, though -- thank you.
> Marshall
-Wm
-
58 matches
Mail list logo
