R.E. Boss,
Very fine, indeed. The big learning opportunity for me was in your
application of dyadic rank to an unadorned argument. As you know (but
other readers may not,) in the example of 2 chs 5 here's what happens:
(]"0 _)&.>/ (i.5) ; i.4
+-------+
|0 1 2 3|
|0 1 2 3|
|0 1 2 3|
|0 1 2 3|
|0 1 2 3|
+-------+
It is great to see the compositional power of (]"0 _) demonstrated so.
Tracy
> I found a more efficient and much more elegant way:
>
> chs=: 4 : ';(,/@:(([,. ]+ <:)"0 _) )&.>/ |.<@i."0 (>:y-x)+i.x'
>
> |: 2 chs 5
> 0 0 0 0 1 1 1 1 2 2 2 2 3 3 3 3 4 4 4 4
> 1 2 3 4 0 2 3 4 0 1 3 4 0 1 2 4 0 1 2 3
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