[Jprogramming] indirect assignment and rank question

[bob therriault]

Good question Linda,

My preference, if you did not need to assign variables, would be to just use the N V V train and so the verb test becomes

   t=:((2 0 1|:])-:(0 1|:]))@:?

and you could apply it to any noun you would like.

   t 3 2 4$5
1

The right inner brackets are not necessary, but I think that they help show the comparison that is taking place a bit more clearly.


Cheers, bob


On 2012-12-07, at 4:56 PM, Linda Alvord wrote:

> Why is it necessary to include  &  in each of these example?
> 
>   (0 1&|:A)-:0 1|:A=:?3 2 4$5 
> 1
>   (2 0 1|:A)-:0 1|:A
> 1
>   (0 1 2|:B)-:3 0 1 2|:B=:?3 2 5 4$5 
> 1
> 
>   (0 1 2&|:B)-:3 0 1 2&|:B=:?3 2 5 4$5 
> 1
> 
> 
> Linda
> 
> -----Original Message-----
> From: programming-bounces at forums.jsoftware.com
> [mailto:programming-bounces at forums.jsoftware.com] On Behalf Of Dan Bron
> Sent: Friday, December 07, 2012 6:05 PM
> To: programming at jsoftware.com
> Cc: programming at jsoftware.com
> Subject: Re: [Jprogramming] indirect assignment and rank question
> 
> Something I never wrapped my head around with |: is what exactly the DoJ
> means when it says axes are "run together" when the LHA is boxed.
> 
> -Dan
> 
> 
> On Dec 7, 2012, at 3:28 PM, Marshall Lochbaum <mwlochbaum at gmail.com> wrote:
> 
>> 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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