Thanks Julian,
Unfortunately Fold doesn’t seem to have made it to the iOS platform yet.
5 f0 i.4
not found:
/private/var/mobile/Containers/Data/Application/84605E1E-B9BA-4FE7-8FFA-1C6C5C0A29E0/Documents/j/addons/dev/fold/foldr.ijs
|nonce error: f0
| 0 x&{{y[1 Z: y > x}} F..+y
load 'foldr'
not found:
/private/var/mobile/Containers/Data/Application/84605E1E-B9BA-4FE7-8FFA-1C6C5C0A29E0/
As a matter of interest what did people use for this facility before F. was
invented?
Richard Donovan
> On 28 Feb 2022, at 18:49, Julian Fondren <[email protected]> wrote:
>
> You can use Fold and the related Z: (Terminate Fold)
>
> 0 {{ y[1 Z: y > 10 }} F.. + 1 5 6 16
> 12
> 0 {{ y[1 Z: y > 10 }} F:. + 1 5 6 16
> 1 6 12
>
> analogous to +/ and +/\ with the argument shortened to where the sum exceeds
> 10:
>
> +/1 5 6
> 12
> +/\1 5 6
> 1 6 12
>
> as a verb:
>
> f0 =: {{ 0 x&{{ y[1 Z: y > x }} F.. + y }}
> 10 f0 1 5 6 16
> 12
> 5 f0 1 5 6 16
> 6
> 100 f0 1 5 6 16
> 28
>
> ------- Original Message -------
>
>> On Monday, February 28th, 2022 at 12:40 PM, Richard Donovan
>> <[email protected]> wrote:
>>
>> I hope someone can enlighten me…
>>
>> If I have a list of numbers, how can I write a verb which will can perform a
>> cumulative sum +/\ which will stop when a target sum is reached?
>>
>> For example, is the list contains 1,5,6,16… I wish to find at what position
>> the cumulative sum exceeds 10. I feel that when I am dealing with monster
>> lists, it would be beneficial if the function could stop as soon as the
>> target had been reached. (If the target was not reached by the end of the
>> list, it would be good if the index of 1 greater than the last item could be
>> returned, as occurs with other j verbs).
>>
>> Thanks in advance,
>>
>> Richard Donovan
>>
>> ----------------------------------------------------------------------
>>
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