I think I should drop a warning flag here:
3 (0 1&{) 2 3 5 7
2 3
3 (0 1&(+:@{)) 2 3 5 7
16 24
http://www.jsoftware.com/help/dictionary/d630n.htm
;)
In other words, the behavior of 2 3&{ in this context might be a bit
surprising if you have oversimplified your understanding of 0 1&{
--
Raul
On Thu, Sep 19, 2013 at 2:25 PM, Pascal Jasmin <[email protected]> wrote:
> Thank you Raul,
>
> The other challenge... placing in column 3 the result of op on first 2
> columns is fairly pretty your way.
>
> 3 +/@(0 1&{)`[`]}"1 i. 4 5
> 0 1 2 1 4
> 5 6 7 11 9
> 10 11 12 21 14
> 15 16 17 31 19
>
>
>
> ----- Original Message -----
> From: Raul Miller <[email protected]>
> To: Programming forum <[email protected]>
> Cc:
> Sent: Thursday, September 19, 2013 2:00:16 PM
> Subject: Re: [Jprogramming] Amend trickiness
>
> On Thu, Sep 19, 2013 at 12:02 PM, Pascal Jasmin <[email protected]>
> wrote:
>> 4 5 $ (+:@(3&{)"1 sel} ,) i. 4 5
>> 0 1 2 6 4
>> 5 6 7 16 9
>> 10 11 12 26 14
>> 15 16 17 36 19
>>
>> is there a gerund amend version that avoids the temp assignments? or other
>> code to get the same result?
>
> In addition to the other proposals, I think this does what you want:
>
> 3 +:@{`[`]}"1 i. 4 5
> 0 1 2 6 4
> 5 6 7 16 9
> 10 11 12 26 14
> 15 16 17 36 19
>
> Note that it can be a little confusing, working through the errors you
> get when experimenting with gerund amend. There's several verbs
> involved, and how do you determine which one is causing the problem?
>
> But you can expand out the definition and inspect what happens that
> way. For example, this was an experiment I almost used:
>
> 3 (4 :'(x{y) (x[y)} x]y'"1) i. 4 5
>
> (But I didn't actually perform that experiment because when I noticed
> that my broken code had an irrelevant ~ in it: 3 +:@{`[`]}"1~ i. 4 5)
>
> I hope this helps,
>
> --
> Raul
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