2 3 5 7 11 13 17 19 23 29 31 37 41 43 47
+/2 3 5 7 1 1 1 1 2 2 3 3 4 4 4
([: +/@:({."1) 10 #.^:_1 p:@:i.) 15
26
(+/@:(<.@:% >:@:<.&.(10&^.))@:p:@:i.) 15
0
2010/11/16 Dan Bron <[email protected]>
> Oh, sorry, thinko: you wanted the first digit, and I gave you the last
> digit. So:
>
> [: +/@:({."1) 10 #.^:_1 p:@:i.
>
> Or you could do something along the lines of:
>
> +/@:(<.@:% >:@:<.&.(10&^.))@:p:@:i.
>
> Of course, I haven't tested any of this, but the fact that I can respond in
> such a manner from my blackberry, on my commute, without the aid of a J
> interpreter, may tell you something about tacit programming.
>
> In other words: using tacit code, we are communicating.
>
> -Dan
>
> PS: Of course, we could also communicate using explicit code or Fortran or
> even standard math notation; it would just be harder to read & write under
> these constraints.
>
> For example, tacit's concise notation allows the reader to quickly spot the
> bug in my initial suggestion (last digit vs first), and similarly allows the
> writer to concisely express abstract concepts like &.(10&^.) .
>
> (And elegantly, if I'm allowed to editorialize)
>
>
> Please excuse typos; composed on a handheld device.
>
> -----Original Message-----
> From: Björn Helgason <[email protected]>
> Sender: [email protected]
> Date: Tue, 16 Nov 2010 12:38:39
> To: Programming forum<[email protected]>
> Reply-To: Programming forum <[email protected]>
> Subject: Re: [Jprogramming] tacit programming
>
> That is not giving the correct answer 43 for the first 15 primes
>
> (10 +/@:#: p:@:i.) 15
> 68
> ([: +/ [: > [: ".&.> [: [ [: {.&.> [: [ [: ":&.>@p: i.) 15
> 43
>
>
>
> 2010/11/16 Dan Bron <[email protected]>
>
> > Björn wrote:
> > > The objective is to get the first number from a list of primes.
> > >
> > > Is there a better way of getting the first number from a list of
> numbers
> > > putting them each in a box than making it first a character and the
> > taking
> > > the first of each element making it a number and summing up the
> resulting
> > > list?
> >
> > I've always preferred to ask for digits directly (numerically), rather
> than
> > projecting into the string domain and returning to the numeric domain:
> >
> > 10 +/@:#: p:@:i.
> >
> > -Dan
> >
> >
> > ----------------------------------------------------------------------
> > For information about J forums see http://www.jsoftware.com/forums.htm
> >
>
>
>
> --
> Björn Helgason, Verkfræðingur
> Fornustekkum II
> 781 Hornafirði,
> t-póst: [email protected]
> gsm: +3546985532
> sími: +3544781286
> http://groups.google.com/group/J-Programming
>
>
> Tæknikunnátta höndlar hið flókna, sköpunargáfa er meistari einfaldleikans
>
> góður kennari getur stigið á tær án þess að glansinn fari af skónum
> /|_ .-----------------------------------.
> ,' .\ / | Með léttri lund verður |
> ,--' _,' | Dagurinn í dag |
> / / | Enn betri en gærdagurinn |
> ( -. | `-----------------------------------'
> | ) | (\_ _/)
> (`-. '--.) (='.'=) ♖♘♗♕♔♙
> `. )----' (")_(") ☃☠
> ----------------------------------------------------------------------
> For information about J forums see http://www.jsoftware.com/forums.htm
> ----------------------------------------------------------------------
> For information about J forums see http://www.jsoftware.com/forums.htm
>
--
Björn Helgason, Verkfræðingur
Fornustekkum II
781 Hornafirði,
t-póst: [email protected]
gsm: +3546985532
sími: +3544781286
http://groups.google.com/group/J-Programming
Tæknikunnátta höndlar hið flókna, sköpunargáfa er meistari einfaldleikans
góður kennari getur stigið á tær án þess að glansinn fari af skónum
/|_ .-----------------------------------.
,' .\ / | Með léttri lund verður |
,--' _,' | Dagurinn í dag |
/ / | Enn betri en gærdagurinn |
( -. | `-----------------------------------'
| ) | (\_ _/)
(`-. '--.) (='.'=) ♖♘♗♕♔♙
`. )----' (")_(") ☃☠
----------------------------------------------------------------------
For information about J forums see http://www.jsoftware.com/forums.htm
