nice.
Ginx=: _2 <\ ;/
(Ginx 2 3 0 5 1 2) {i.5 6
15 5 8
----- Original Message -----
From: Nollaig MacKenzie <[email protected]>
To: [email protected]
Cc:
Sent: Thursday, May 29, 2014 1:27:46 PM
Subject: Re: [Jprogramming] Indexing into array
I use
Ginx=: <"0&.>@<"1
(Ginx 2 2$1 2 2 3){i.3 5
7 13
On 2014.05.29 11:15:22, you,
the extraordinary alexgian, spake thus:
> If I want to index into a (rank 2) array to get the element usually called
> the (i,j)th in the big, bad world, is there a better way to do it than
> this, which I currently use?
>
> idx =: (1 { [) { ] {~ 0 { [
>
> 2 1 idx 4 4 $i.16
>
> 9
>
> I notice that if { takes an array as left arg, it merely returns the given
> rows of that array, rather than the required indexed element.
> So I can't do, for instance, (2 1) { 4 4 $i.16 and get what I want
> Furher, I wander if there is a more generic way of writing this so that it
> would work automatically for rank-3 arrays and greater.
--
Nollaig MacKenzie
http://www.yorku.ca/nollaig
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