as for the trailing 5s:
i: needs to fill with trailing 0s so you intermediately get
_2 _1 0 1 2
_2 0 2 0 0
adding 5 leads to your result
I once wrote this (here adjusted to Ruda’s example)
in case stepping is used really frequently
throughout the code — but there is too much
(two multiplications and one addition on the vector)
happening after cut01 so it’s not worth the effort
NB. say we have y = 4 and want to get 0 0.25 0.5 0.75 1
cut01 =: (% * i.@>:) M.
NB. say we have x = 14 and y = 3 and want to get 0 3 6 9 12
steps =: ([ - |~) ([ * cut01@%) ]
NB. say we have x = 5 19 and y = 3 want to get 5 8 11 14 17
stepThrough =: {.@[ + <:@+:@</@[ * |@-/@[ steps ]
Am 29.03.20 um 12:39 schrieb 'Michael Day' via Programming:
I was thinking that i: with a complex argument would get you there, eg:
5+i:2 2j2
3 4 5 6 7
3 5 7 5 5 NB. why the trailing 5s?
but bending it to your wishes looks a bit tricky.
I vaguely recalled there was a utility verb, "steps." I've found it in
various addons;
I think it's in one of the standard libraries, too:
steps=: {. + (1&{ - {.) * (i.@>: % ])@{:
steps 3 7 2
3 5 7
steps 3 7 3
3 4.33333 5.66667 7
I see someone else has just posted, but I'll send this anyway, having
spent a few minutes on it!
Cheers,
Mike
On 29/03/2020 10:52, Rudolf Sykora wrote:
Dear all,
how do you usually generate a sequence of integers from 'a' to 'b' with
a step 's'?
If I ignore the step, yesterday I wrote
interval=.{.+(i. @ >: @ ({:-{.))
interval 5 19
5 6 7 8 9 10 11 12 13 14 15 16 17 18 19
but that seems overly complicated...
Then I can include the step in this way
_3 {.\ interval 5 19
5 8 11 14 17
Putting the two parts together would make it even more complicated.
There must be a better way...
Thanks
Ruda
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