So you probably just need this:
f=:(] +:@{`[`]} <@<@<@]{[)"_ 0 [:I.2=/\]
or really the adverb
a=:1 :'u@(] +:@{`[`]} <@<@<@]{[)"_ 0 [:I.2=/\]'
You may find different solutions if you abstract your problem differently.
> On Nov 7, 2016, at 9:30 PM, Skip Cave <[email protected]> wrote:
>
> Very interesting. Quite a difference in space and time usage, not to
> mention length of the tacit code.
>
> For my application, a rank 0 or 1 in the summed result isn't all that
> critical. As long as the contents of each box can be used in further
> arithmetic and Boolean operations (e.g. it's not text), then I'm ok.
>
>
> It looks like nouns with ranks 0 or 1 don't affect the outcome of simple
> arithmetic operations:
>
>
> ($4);($,4);(4=,4);(1+4);(1+,4);((1+4)=1+,4);($1+4);($1+,4)
>
> ┌┬─┬─┬─┬─┬─┬┬─┐
>
> ││1│1│5│5│1││1│
>
> └┴─┴─┴─┴─┴─┴┴─┘
>
> The only time the difference becomes an issue:
>
> ($4)=($,4)
>
> |length error
>
> | ($4) =($,4)
> But I don't care about this.
>
> Actually, Mike Day spotted what I was really trying to attempt.
> The original starting vector is:
>
> n =: 1 2 2 4 1 5 3 4 4 4 2 3 3
>
> Then I box at each possible pair of integers using an infix sliding-window
> on each pair of integers. This sliding box scheme was just to identify all
> the duped pairs in the original vector.
>
> ]N =: 2<\pp
>
> ┌───┬───┬───┬───┬───┬───┬───┬───┬───┬───┬───┬───┐
>
> │1 2│2 2│2 4│4 1│1 5│5 3│3 4│4 4│4 4│4 2│2 3│3 3│
>
> └───┴───┴───┴───┴───┴───┴───┴───┴───┴───┴───┴───┘
>
>
> What I ultimately wanted is a verb that will replace the duped pairs in the
> *original* un-boxed vector, one at a time:
>
> n =: 1 2 2 4 1 5 3 4 4 4 2 3 3
>
> f n
>
> 1 4 4 1 5 3 4 4 4 2 3 3
>
> 1 2 2 4 1 5 3 8 4 2 3 3
>
> 1 2 2 4 1 5 3 4 8 2 3 3
>
> 1 2 2 4 1 5 3 4 4 4 2 6
>
> Of course, the final row lengths will be one shorter that the original row
> length.
>
> Skip
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