Hi Piet,
I am not sure how simple it is, but combining Rob's excellent insight on
oblique with Transpose, Under and rank 1 you get this:
(*:`-:`^ /.)"1 &. |: i. 3 5
0 1 4 9 16
2.5 3 3.5 4 4.5
22026.5 59874.1 162755 442413 1.2026e6
The transpose works in this case because the 3 gerunds are applied to each
transposed row and then Under (&.) undoes the transpose to provide the results
in a shape of 3 5
Cheers, bob
> On May 2, 2019, at 10:15 PM, Piet de Jong <[email protected]> wrote:
>
> Thanks! But it doesn’t appear to generalise to applying successive verbs in
> the gerund to successive >>items<< in y.
>
> (I checked the dictionary re /. and it talks of “collections” of y. Not
> sure what that means)
>
> For example if y is i.3 5 then I’d like the first verb in the gerund to apply
> to the first item of y, the second verb to the second item, and so on.
>
> Is there a simple solution for this?
>
>> On 3 May 2019, at 12:35 pm, 'Rob Hodgkinson' via Programming
>> <[email protected]> wrote:
>>
>> Hi Piet, not ignorant at all !
>>
>> Try using oblique (an obscure feature is that the u in u/. can be a gerund,
>> in which case it is evoked cell wise);
>>
>> g=. *: ` -: `^
>> y=. 3 1 0
>> g /. y
>> 9
>> 0.5
>> 1
>>
>> Found in Section 15 of https://www.jsoftware.com/books/pdf/brief.pdf
>> <https://www.jsoftware.com/books/pdf/brief.pdf>.
>>
>> HTH, Regards Rob
>>
>>> On 3 May 2019, at 10:59 am, pietdion <[email protected]> wrote:
>>>
>>> Hopefully not an ignorant question.
>>>
>>> Am looking for a simple (tacit, non complicated) construction (verb?
>>> adverb? conjunction?) “c" that takes a gerund and applies the successive
>>> verbs in the gerund to successive items.
>>>
>>> A simple example is
>>>
>>> g=. *: ` -: `^
>>> y=. 3 1 0
>>> g c y
>>> 9 0.5 1
>>>
>>> What “c” achieves this for arbitrary gerunds g's and y’s?
>>>
>>> I realise this can be done in a variety of explicit ways and with the
>>> agenda construct. All I can come up with is intricate constructions.
>>> Looking for something simple and direct. Seems to have a lot of uses.
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