NYCJUG's own Will Gajate presented some work on folds recently: https://code.jsoftware.com/wiki/User:Will_Gajate/FoldVariants . Please take a look and feel free to embellish.
On Fri, Feb 5, 2021 at 4:06 PM Henry Rich <[email protected]> wrote: > I will be happy for you guys to do whatever you think makes the > documentation best. We are all beginners with Fold. > > hhr > > On 2/5/2021 1:19 PM, Hauke Rehr wrote: > > I strongly support this. Folds belong at the core > > of any functional language but I didn’t use them > > since I got used to doing things differently > > when they hadn’t been around; and when they were > > introduced, I, too, was disappointed by the lack > > of easily understood and adaptable examples. > > At least that’s the way things were then. > > But I was happy seeing them introduced. > > > > On one thing, I disagree, though. > > They may share that common umbrella page, > > but I think it should point to six subpages. > > The way I (don’t) understand them, they are > > conceptually too close for users to be taught > > about them seperately. > > > > Am 05.02.21 um 19:06 schrieb Raul Miller: > >> I've been thinking about > >> https://code.jsoftware.com/wiki/Vocabulary/fcap and some of my > >> struggles with it, in its current form. > >> > >> (1) The page covers six different conjunctions, and does not begin to > >> give examples until half way down the page. > >> > >> Conceptually, I would prefer a page dedicated to each in the > >> vocabular, with the diagrams from this page as reference material > >> elsewhere (perhaps an appendix, perhaps a lab, perhaps an introductory > >> document, perhaps repeated from each vocabulary page, perhaps > >> something else). > >> > >> (2) Although the page includes a statement suggesting that it's better > >> to use the dyad form of a fold multiple verb than the monad form, the > >> page contains no worked examples using the dyad form (for example: > >> using numbers or characters). > >> > >> (3) The u argument is an efficiency mechanism, which means sometimes > >> it's best to not use it and put the efficiency elsewhere. > >> > >> (4) The result of the monad use of a fold multiple verb is 1 less than > >> the length of the original list, and that can be useful but it can > >> also take some getting used to. The result of the dyad use of a fold > >> multiple verb is the same length as the y argument. > >> > >> #]F:.,: i.12 > >> 11 > >> #1 ]F:.,: i.12 > >> 12 > >> > >> ---------------------------- > >> > >> Anyways, I think we need some good canonical examples of use for these > >> conjunctions, so that people can see how things work. > >> > >> (I'll see if I can come up with something... but for now I wanted to > >> leave this here, before I forget about these issues, again.) > >> > >> Do any of you have a nice example or two? > >> > >> Thanks, > >> > > > -- > This email has been checked for viruses by AVG. > https://www.avg.com > > ---------------------------------------------------------------------- > For information about J forums see http://www.jsoftware.com/forums.htm > -- Devon McCormick, CFA Quantitative Consultant ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm
