Yep - a blocky approach addresses the virtues of a vector approach and
minimises the hit with extended. Could fine tune it but why bother!?
I quite often end up using blocks in this sort of fashion, though
overlooked
it here.
Note to self, though - must look into why /\. with reverse is better!
Thanks again, Raul,
Mike
On 16/05/2017 17:04, Raul Miller wrote:
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,
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