If you think of ;.n as being 4 different adverbs based on n, you can use the appropriate names for each.  NuVoc uses 'Subarray' for dyadic u;.0 .

Henry Rich

On 1/1/2019 3:40 PM, Devon McCormick wrote:
If I wanted to have "cut" without overtake, I'd be happier, upon
encountering the code later, if I had written a well-named helper verb -
maybe even documented it - rather than spend the time trying to puzzle out
what I had earlier intended with a non-obvious use of "cut".

On Tue, Jan 1, 2019, 14:54 'Pascal Jasmin' via Programming <
[email protected] wrote:

seems better than what I've been doing,

take
(*@[ * |@[ <. #@:]) {. ]



$ 2 take i.0
0

take =: ];.0 :: (i.@(0"_) )

$ 2 take i.0

0


it loses negative indexing though, so

take =: (];.0)`(];.0)`(] {.~ _1: * |@[ <. #@:])@.(*@[)^:(0 < #@])

_7 take i.6
0 1 2 3 4 5
_3 take i.6
3 4 5

_3 take i.0


3 take i.2 2
0 1
2 3


________________________________
From: Igor Zhuravlov <[email protected]>
To: Jprogramming <[email protected]>
Sent: Saturday, December 29, 2018 9:02 PM
Subject: [Jprogramming] Cut (;.) behavior consistency



A Cut (;.) is a convenient alternative to Take ({.) when there is a need
to ignore overtake:


    4 {. i. 3

0 1 2 0

    4 ];.0 i. 3

0 1 2


But is Cut's behavior consistent?:


    2 ];.0 i. 2

0 1                 NB. ok

    2 ];.0 i. 1

0                   NB. ok

    2 ];.0 i. 0

|index error

| 2 ];.0 i.0


Shouldn't result be an empty list instead of error? However, the following
works:


    0 ];.0 i. 0

                     NB. empty list, ok


--

Regards,

Igor

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