Hi Jan-Pieter, thank you for your help.
This why I am trying to understand how to use the keyboard facilities. The
keyboard input ((1:1) 1) treats its input as literals. If you run my
function you will understand the behavior.
extd =: 4 : 0
n=. ((1:1) 1)
((".@,&'x' n)) A. i. x
)
Ak
On Mon., Aug. 14, 2023, 15:28 Jan-Pieter Jacobs, <janpieter.jac...@gmail.com>
wrote:
> Let me try to explain it :
>
> The moment J parses a number that iss not followed by an x, it will never
> be
> an extended integer. This is irrespective of whether the number is parsed
> on the command line (J's term), via ". from a string, or from a script.
> Loosely speaking, whenever you want a typed-in number to be extended, you
> have to explicitly tell J it is one, by following the number with an x.
> This is irrespective of the function that operates later on this number
> (like the ones you listed).
>
Yes. This is why I tr
> If a number *is* already extended (and stored in a variable, or passed from
> the function that created it to the next), operations performed on it will
> keep it extended. A. appears to be one of only a few verbs that creates an
> extended integer when not fed one (the only other one I can think of is
> x:).
>
> Another thing that could be of help is the linear representation (5!:5),
> which returns a string which, when parsed, returns the exact value of the
> variable passed as it's argument. A short recording of my session:
>
> r=:A. p=:?~ 30 NB. a permutation number and vector
> datatype r NB. returned datatype is:
> extended
> r NB. simple display representation
> 162474627391890403202250095642096
> 5!:5 <'r' NB. linear representation that can be used to get the exact
> value of the variable r, which includes indeed an x
> 162474627391890403202250095642096x
> datatype 162474627391890403202250095642096 NB. copied and pasted in the
> J term, results in a float, loosing precision because the number is too
> large.
> floating
> r-:!.0]162474627391890403202250095642096 NB. indeed the number is not
> the same as r
> 0
> datatype ".'162474627391890403202250095642096' NB. the same when parsed
> using ".
> floating
>
> datatype ". 5!:5<'r' NB. do linear representation does maintain
> precision.
> extended
>
> r=!. 0 ". 5!:5<'r' NB. indeed the same number.
> 1
>
> Long story short: if you want precise numbers, append an x or store an
> already precise number in a variable. Don't rely on copy-pasting J's
> output, because it is not meant for being interpretable by J like it is in
> some other languages. Extended numbers aren't the only instance: arrays >
> rank 1 cannot be parsed directly in their display form either. The same for
> strings (litterals in J's parlance), as the ticks (') are omitted for
> display.
>
> I hope this helps.
>
> Jan-Pieter
>
> On Mon, 14 Aug 2023, 22:19 Ak O, <akin...@gmail.com> wrote:
>
> > Thank you for this idea but it does not cover this case. Your input is
> not
> > long enough.
> > t=:{{":y}}
> > t 180548043269214561950911457875657
> > 1.80548e32
> >
> > The object is to achieve 180548043269214561950911457875657x
> > in a defined function, so that the input
> 180548043269214561950911457875657
> > is treated as 180548043269214561950911457875657x.
> >
> >
> > If you run each function that I gave below with the inputs I have given
> you
> > will see what I mean.
> >
> > This where the numbers come from.
> > ] permuted_vector. =: ?.~30
> > 20 12 4 29 7 17 22 11 2 27 28 23 6 21 9 3 24 10 26 13 15 1 18 8 25 19 0 5
> > 16 14
> >
> > ] A. permuted_vector
> > 180548043269214561950911457875657
> >
> >
> >
> > Now we need to go back.
> >
> > ] (A. permuted_vector) A. i. 30
> > 20 12 4 29 7 17 22 11 2 27 28 23 6 21 9 3 24 10 26 13 15 1 18 8 25 19 0 5
> > 16 14
> >
> > (A. permuted_vector) is extended by output construction of (A.).
> > So it feeds naturally to the dyadic (A.) operator. This always produces
> the
> > same permuted_vector.
> >
> > The challenge is feeding an extended input to the dyad.
> > After a length of 19 digits, the type degrades to a float.
> >
> >
> > So please try your own permuted_vector of length minimum 30 with these
> > functions below. Their behavior mightshow where my ideas are misplaced.
> >
> >
> > Function 1
> >
> > Step 1. Run
> >
> > extd =: 4 : 0
> > n=. ((1!:1) 1
> > ((".@,&'x' n)) A. i. x
> > )
> >
> > Step 2. Run
> > 30 extd 180548043269214561950911457875657
> >
> >
> > Step 3. Input and enter.
> > 180548043269214561950911457875657
> >
> > Complete.
> >
> >
> >
> > Function 2
> >
> > Step 1. Run
> >
> > extdquotes =: 4 : 0
> > ((".@,&'x' n)) A. i. x
> > )
> >
> > Step 2. Run.
> > 30 extdquotes '180548043269214561950911457875657'
> >
> >
> > Complete.
> >
> >
> > I might not be explaining as clearly as possible, I appreciate your
> > patience.
> >
> >
> >
> > Ak.
> >
> >
> >
> >
> >
> > On Mon., Aug. 14, 2023, 12:34 'Skip Cave' via Programming, <
> > programm...@jsoftware.com> wrote:
> >
> > > t=.{{":y}}
> > >
> > > t 12345678987654321
> > >
> > > 12345678987654321
> > >
> > >
> > > datatype t 12345678987654321
> > >
> > > literal
> > >
> > >
> > > Skip Cave
> > > Cave Consulting LLC
> > >
> > >
> > > On Mon, Aug 14, 2023 at 1:29 PM Gilles Kirouac <g1...@myriade.ca>
> wrote:
> > >
> > > > >>> What expression allows a function to recieve an argument 'y' as
> a
> > > > literal
> > > > >>> without using quotes?
> > > >
> > > > None.
> > > >
> > > > BTW, do not rely on the output of ": (default format) to determine
> the
> > > > type, because it uses a default format with a default precision. Use
> > > > datatype instead
> > > >
> > > > datatype 180548043269214561950911457875657
> > > > floating
> > > > datatype 18054843269214561950911457875657x
> > > > extended
> > > > 34j0 ": 1805480403269214561950911457875657
> > > > 18054804326921457349416459226316 NB. loss of precision after 15
> > digits
> > > > 34j0 ": 180548043269214561950911457875657x
> > > > 180548043269214561950911457875657 NB. no loss of precision
> > > >
> > > >
> > > >
> > > > ~ Gilles
> > > >
> > > > Le 2023-08-14 à 14:00, Ak O a écrit :
> > > > > Unfortunately ": does not work in this case.
> > > > > The length of the input causes the input to be treated as a float.
> > The
> > > > > result is:
> > > > >
> > > > > ": 180548043269214561950911457875657
> > > > > 1.80548e32
> > > > >
> > > > >
> > > > >
> > > > > On Mon., Aug. 14, 2023, 11:16 'Skip Cave' via Programming, <
> > > > > programm...@jsoftware.com> wrote:
> > > > >
> > > > >> ":y converts an integer in y into a literal.
> > > > >>
> > > > >> Skip Cave
> > > > >> Cave Consulting LLC
> > > > >>
> > > > >>
> > > > >> On Mon, Aug 14, 2023 at 11:58 AM Ak O <akin...@gmail.com> wrote:
> > > > >>
> > > > >>> What expression allows a function to recieve an argument 'y' as a
> > > > literal
> > > > >>> without using quotes?
> > > > >>>
> > > > >>> Below are two deficient functions.
> > > > >>> The size of the vector is given by 'x'. The permutation
> > > > >>> index is meant to be given by 'y'.
> > > > >>>
> > > > >>> My intention is treat 'y' as a literal, without needing to use
> > quotes
> > > > on
> > > > >>> the input.
> > > > >>>
> > > > >>> This first function works by escaping to the keyboard for input
> > > > >>> I would like rather for the function to receive the input from
> the
> > > raw
> > > > >>> argument and not have to escape to the keyboard.
> > > > >>>
> > > > >>> Desired Input
> > > > >>> 30 extd 180548043269214561950911457875657
> > > > >>> Rather than
> > > > >>> 30 extd '180548043269214561950911457875657'
> > > > >>>
> > > > >>>
> > > > >>> This function is deficient by its operating sequence.
> > > > >>> It escapes to keyboard, which preservs the literal type.
> > > > >>>
> > > > >>> extd =: 4 : 0
> > > > >>> n=. ((1!:1) 1
> > > > >>> ((".@,&'x' n)) A. i. x
> > > > >>> )
> > > > >>>
> > > > >>> 30 extd 180548043269214561950911457875657
> > > > >>>
> > > > >>> Keyboard input (if this approach makes sense, can the keyboard
> > input
> > > > be
> > > > >>> simulated by using y as the feed?)
> > > > >>> 180548043269214561950911457875657
> > > > >>>
> > > > >>> Result
> > > > >>> 20 12 4 29 7 17 22 11 2 27 28 23 6 21 9 3 24 10 26 13 15 1 18 8
> 25
> > 19
> > > > 0 5
> > > > >>> 16 14
> > > > >>>
> > > > >>>
> > > > >>>
> > > > >>> Alternative deficient function by the input form.
> > > > >>> Yields the correct result but uses quotes in the input.
> > > > >>>
> > > > >>> extdquotes =: 4 : 0
> > > > >>> ((".@,&'x' n)) A. i. x
> > > > >>> )
> > > > >>>
> > > > >>> 30 extdquotes '180548043269214561950911457875657'
> > > > >>>
> > > > >>> Result
> > > > >>> 20 12 4 29 7 17 22 11 2 27 28 23 6 21 9 3 24 10 26 13 15 1 18 8
> 25
> > 19
> > > > 0 5
> >
> >
> > > > >>>
> >
> > > >>> 16 14
> > > > >>>
> > > > >>> I am looking for the function that uses the input for extd that
> > > > delivers
> > > > >>> the result of extdquotes
> > > > >>>
> > > > >>>
> > > > >>> Thank you for your help
> > > > >>> Ak
> > > > >>>
> > > > ...
> > > >
> ----------------------------------------------------------------------
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> > > >
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