What about something like this?
(|.~ ,.@i.@#)&.> n
┌─────┬─────────┬───┬───────┐
│1 2 3│4 5 6 7 8│8 6│3 5 7 9│
│2 3 1│5 6 7 8 4│6 8│5 7 9 3│
│3 1 2│6 7 8 4 5│ │7 9 3 5│
│ │7 8 4 5 6│ │9 3 5 7│
│ │8 4 5 6 7│ │ │
└─────┴─────────┴───┴───────┘
Skip Cave <[email protected]> wrote:
> Is there a more concise way to express m rotations of each of a set of
> items?
>
> ]n=.1 2 3;4 5 6 7 8;8 6;3 5 7 9
>
> ┌─────┬─────────┬───┬───────┐
>
> │1 2 3│4 5 6 7 8│8 6│3 5 7 9│
>
> └─────┴─────────┴───┴───────┘
>
> m=. 0, 1, 2, 3, 4 NB. Number of rotations
>
> ea =. each
>
>
> n,.(1|.ea n),.(2|.ea n),.(3|.ea n),.(4|.ea n)
>
> ┌─────────┬─────────┬─────────┬─────────┬─────────┐
>
> │1 2 3 │2 3 1 │3 1 2 │1 2 3 │2 3 1 │
>
> ├─────────┼─────────┼─────────┼─────────┼─────────┤
>
> │4 5 6 7 8│5 6 7 8 4│6 7 8 4 5│7 8 4 5 6│8 4 5 6 7│
>
> ├─────────┼─────────┼─────────┼─────────┼─────────┤
>
> │8 6 │6 8 │8 6 │6 8 │8 6 │
>
> ├─────────┼─────────┼─────────┼─────────┼─────────┤
>
> │3 5 7 9 │5 7 9 3 │7 9 3 5 │9 3 5 7 │3 5 7 9 │
>
> └─────────┴─────────┴─────────┴─────────┴─────────┘
>
>
> Or better yet with no duplicated rotations::
>
> 2 7$~.,n,.(1|.ea n),.(2|.ea n),.(3|.ea n),.(4|.ea n)
>
> ┌─────────┬─────┬─────┬─────────┬─────────┬─────────┬─────────┐
>
> │1 2 3 │2 3 1│3 1 2│4 5 6 7 8│5 6 7 8 4│6 7 8 4 5│7 8 4 5 6│
>
> ├─────────┼─────┼─────┼─────────┼─────────┼─────────┼─────────┤
>
> │8 4 5 6 7│8 6 │6 8 │3 5 7 9 │5 7 9 3 │7 9 3 5 │9 3 5 7 │
>
> └─────────┴─────┴─────┴─────────┴─────────┴─────────┴─────────┘
>
> Can this be done using iteration rather than explicitly listing each
> rotation?
>
> Skip Cave
> Cave Consulting LLC
> ----------------------------------------------------------------------
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