Thank you I think it's going better, or at least I'm understanding a bit more.
The problem I had was another, quicksort was sending the whole list to compare inside comp2. I fixed it with these: quickp=: 3 : 0 if. 1 >: #y do. y else. (quickp y lesser sel e),(y equal sel e),quickp y greater sel e=.y{~?#y end. ) lesser=:{{1=>x comp2 each y}} equal=:{{2=>x comp2 each y}} greater=:{{0=>x comp2 each y}} Now the problem is another. I can find the element inside the original list, but I can't search inside the sorted list, or store the sorted list. quickp pp ┌┬──┬────┬───────────┬───────────┬─────────────┬─────────────────────────────┬─────────────────────────────┬───────┬───┬─┬─────────────┬───────────────┬───┬───────┬─────────┬─────────┬─┐ ││┌┐│┌──┐│┌─┬─┬─┬─┬─┐│┌─┬─┬─┬─┬─┐│┌───┬───────┐│┌─┬─────────────────────┬─┬─┐│┌─┬─────────────────────┬─┬─┐│┌───┬─┐│┌─┐│3│┌───────┬─┬─┐│┌───────┬─┬─┬─┐│┌─┐│┌─┬─┬─┐│┌─┬─┬─┬─┐│┌───────┐│9│ ││││││┌┐│││1│1│3│1│1│││1│1│5│1│1│││┌─┐│┌─┬─┬─┐│││1│┌───────────────────┐│8│9│││1│┌───────────────────┐│8│9│││┌─┐│4│││2││ ││┌─────┐│4│4│││┌─────┐│4│4│4│││6│││7│7│7│││7│7│7│7│││┌─┬─┬─┐││ │ ││└┘││││││└─┴─┴─┴─┴─┘│└─┴─┴─┴─┴─┘│││1│││2│3│4││││ ││┌─┬───────────────┐││ │ │││ ││┌─┬───────────────┐││ │ ││││1││ ││└─┘│ │││┌─┬─┐││ │ ││││┌─┬─┐││ │ │ ││└─┘│└─┴─┴─┘│└─┴─┴─┴─┘│││8│7│6│││ │ ││ ││└┘││ │ ││└─┘│└─┴─┴─┘│││ │││2│┌─┬───────────┐│││ │ │││ │││2│┌─┬───────────┐│││ │ │││└─┘│ ││ │ ││││4│4│││ │ │││││4│4│││ │ │ ││ │ │ ││└─┴─┴─┘││ │ ││ │└──┘│ │ │└───┴───────┘││ │││ ││3│┌─┬───────┐││││ │ │││ │││ ││3│┌─┬───────┐││││ │ ││└───┴─┘│ │ │││└─┴─┘││ │ ││││└─┴─┘││ │ │ ││ │ │ │└───────┘│ │ ││ │ │ │ │ ││ │││ ││ ││4│┌─┬─┬─┐│││││ │ │││ │││ ││ ││4│┌─┬─┬─┐│││││ │ ││ │ │ ││└─────┘│ │ │││└─────┘│ │ │ ││ │ │ │ │ │ ││ │ │ │ │ ││ │││ ││ ││ ││5│6│0││││││ │ │││ │││ ││ ││ ││5│6│7││││││ │ ││ │ │ │└───────┴─┴─┘│└───────┴─┴─┴─┘│ │ │ │ │ │ ││ │ │ │ │ ││ │││ ││ ││ │└─┴─┴─┘│││││ │ │││ │││ ││ ││ │└─┴─┴─┘│││││ │ ││ │ │ │ │ │ │ │ │ │ │ ││ │ │ │ │ ││ │││ ││ │└─┴───────┘││││ │ │││ │││ ││ │└─┴───────┘││││ │ ││ │ │ │ │ │ │ │ │ │ │ ││ │ │ │ │ ││ │││ │└─┴───────────┘│││ │ │││ │││ │└─┴───────────┘│││ │ ││ │ │ │ │ │ │ │ │ │ │ ││ │ │ │ │ ││ ││└─┴───────────────┘││ │ │││ ││└─┴───────────────┘││ │ ││ │ │ │ │ │ │ │ │ │ │ ││ │ │ │ │ ││ │└───────────────────┘│ │ │││ │└───────────────────┘│ │ ││ │ │ │ │ │ │ │ │ │ │ ││ │ │ │ │ │└─┴─────────────────────┴─┴─┘│└─┴─────────────────────┴─┴─┘│ │ │ │ │ │ │ │ │ │ │ └┴──┴────┴───────────┴───────────┴─────────────┴─────────────────────────────┴─────────────────────────────┴───────┴───┴─┴─────────────┴───────────────┴───┴───────┴─────────┴─────────┴─┘ sorted=:quickp pp |domain error: comp2 | ({.tx) <{.ty cder'' 0 0 (1+i.#pp)*2=1 a&comp2\ quickp pp |domain error: comp2 | ({.tx) <{.ty So... any idea how to continue? Rest of my code is in https://github.com/JaumeGreen/adventofcode/tree/master/2022/day13 mostly in explanation, but some of the newer changes only in log. Thanks. Missatge de Raul Miller <rauldmil...@gmail.com> del dia dt., 13 de des. 2022 a les 20:00: > p.s. for the tacit stack issue, you did not include your definition of > comp2, but if it's from aoc day 13, a plausible issue is that comp2 > would be returning _1 or 1 instead of 0 or 1 (which is what that > quicksort implementation expects). > > That said, when debugging stack errors on recursive functions, it can > be handy to use $:&([echo) so that you can see where the spam where > the recursion goes wrong. > > -- > Raul > > On Tue, Dec 13, 2022 at 1:43 PM Jaume <greenni...@gmail.com> wrote: > > > > Hello all > > > > Still here and I've done all the days in J except for day 7, But that's > not > > why I'm here. > > > > So now I've done the first part, and I have a function that is too long > to > > copy that does comparisons in an iterative way (I had some stack > problems). > > Now I'm wanting to sort the elements using this function, but I don't > know > > how. > > > > All the sorting is done using the standard comparison, all the grading is > > numerical, the quicksort implementation in > > https://www.jsoftware.com/help/dictionary/cif.htm (and in > > https://code.jsoftware.com/wiki/Essays/Quicksort) is giving me an error > > even when trying with numbers. > > > > sel=: 1 : 'x # [' > > > > quicksort=: 3 : 0 > > > > if. 1 >: #y do. y > > > > else. > > > > (quicksort y <sel e),(y =sel e),quicksort y >sel e=.y{~?#y > > > > end. > > > > ) > > > > quicksort 15 2 9 10 4 0 13 13 18 7 > > > > |noun result was required: quicksort > > > > | x#[ > > > > |[-0] > > > > > > And the tacit version, which I hope I modified correctly, it's also > giving > > me a stack error. > > > > less=:{{x comp2 y}} > > > > great=:{{y comp2 x}} > > > > quicksort=: (($:@(less#[) , (=#[) , $:@(great#[)) ({~ ?@#)) ^: (1<#) > > > > quicksort pp > > > > |stack error: comp2 > > > > | y comp2 x > > > > > > Any idea how can I sort the elements or correct the errors I have? > > > > Thanks > > ---------------------------------------------------------------------- > > For information about J forums see http://www.jsoftware.com/forums.htm > ---------------------------------------------------------------------- > For information about J forums see http://www.jsoftware.com/forums.htm > -- The fact that an opinion has been widely held is no evidence whatever that it is not utterly absurd. -- Bertrand Russell ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm