Oops, need x: instead of <.
|. 281474976710656&|@*/\.x:1+2*i.-2^24
Sorry about that, was using <. earlier to test whether that fixed the
overflow issue (it does not), and grabbed that instance for this
variant.
This is bulkier, though, just like your */\ version:
timespacex'|. 281474976710656&|@*/\.x:1+2*i.-2^12'
0.005394 2.72333e6
datatype |. 281474976710656&|@*/\.x:1+2*i.-2^12
extended
And if I could think of an efficient way of demoting the result type
to integer, I think I could use that reduce some of the bulk.
Sadly, though, the obvious approach doesn't do it:
timespacex'|. 281474976710656&|@*/\.&.x:1+2*i.-2^12'
0.004687 2.65882e6
Still... why not break this into pieces?
Something like (warning, untested code):
genseries=:3 :0
r=. ''
n=.1
for. i.2^6 do.
r=. r,|. 281474976710656&|@*/\.&.x:n+2*i.-2^18
n=. {:r
end.
r
)
Thanks,
--
Raul
On Tue, May 16, 2017 at 11:38 AM, 'Mike Day' via Programming
<[email protected]> wrote:
> It would be nice if it worked.
>
> Unfortunately (again!), for the actual size required,
>
> timer'_10{. |. 281474976710656&|@*/\.<.1+2*i.-2^24'
> +------+-------------------+
> |32.001|0 0 0 0 0 0 0 0 0 0|
> +------+-------------------+
>
> whereas the correct values are all > 0
>
> This is why I needed special code, either using extended
> integers and then making the results simple 64-bit integer,
> or using a mask and shift method and working on 24-bit
> components.
>
> Pity!
>
> Thanks,
>
> Mike
>
> On 16/05/2017 15:42, Raul Miller wrote:
>>
>> timespacex'|. 281474976710656&|@*/\.<.1+2*i.-2^12'
>> 0.00096 331904
>> (281474976710656&|@*/\x:1+2*i.2^5) -: |.
>> 281474976710656&|@*/\.<.1+2*i.-2^5
>> 1
>>
>> I hope this helps,
>>
>
>
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