That (using /.) is what I was going to say.
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({."1 ]/. {:"1) a,b
Thanks,
--
Raul
On Tue, Aug 12, 2014 at 6:36 PM, robert therriault
<[email protected]> wrote:
> Hi Joe,
>
> Henry touches on this in JforC: Apply On Subsets: Dyad u/.
>
> http://www.jsoftware.com/help/jforc/loopless_code_v_partitions.htm#_Toc191734451
>
> He does a total instead of an append, but I think you'll get the idea.
>
> Cheers, bob
>
> On Aug 12, 2014, at 3:19 PM, Joe Bogner <[email protected]> wrote:
>
>> I've been fiddling with this for 30 minutes and I can't figure it
>> out... Maybe it's too late in the day
>>
>> a=:_2]\'a';1;'b';2;'c';3
>> b=:_2]\'c';5;'a';4
>>
>> what verb will produce this?
>>
>> ]a,.(4;'';5)
>> ┌─┬─┬─┐
>> │a│1│4│
>> ├─┼─┼─┤
>> │b│2│ │
>> ├─┼─┼─┤
>> │c│3│5│
>> └─┴─┴─┘
>>
>>
>> I went down this path:
>>
>> ] ((0{"1 b)i.(0{"1 a))
>> 1 2 0
>>
>> I figured I could use { and return '' if the index was greater than
>> the length (e.g., 2 should be '')
>>
>> I tried using :: to return '' on index error but I couldn't get that to work
>>
>> NB. not what I wanted
>> ] ((0{"1 b)i.(0{"1 a)) ({ :: ('no'"_)) b
>> no
>>
>> Then I tried using ^: to return '' if the length was greater than # b
>>
>> Then I tried writing a explicit verb using if.
>>
>> Then I threw in the towel and decided to ask for help since this must
>> be a common need
>>
>> I'm sure I've solved this before but cannot remember how
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>
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