[Jprogramming] indirect assignment and rank question

[Marshall Lochbaum]

0 1 2&|: will do the job.

I recommend reading the dictionary definition of |: through a few times.
In particular, note that 0 1&|: on a rank three array is the same as
2 0 1&|: , and 0 1 2&|: turns into 3 0 1 2&|: on a rank four array.

Marshall

On Fri, Dec 07, 2012 at 03:02:49PM -0500, Brian Schott wrote:
> I am working with photographic images which use RGB color.
> The array d is a single image and the array D is now 2 images but I
> want D to contain any number of images. And I want split out the
> R,G, and B part which I can do for d, but I am having difficulty
> with the analogous r, g, and b for D.
> 
>    $d
> 50 50 3
>    $D
> 2 50 50 3
> 
>    'R G B'=: 0 1|: d
>    $G
> 50 50
> 
> What is the mysteryverb that will produce ($g)-:2 50 50 in the
> following expression?
>    'r g b'=: mysteryverb D
> 
> Thanks,
> 
> (B=)
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