if you want the index rather than the coordinate values, then
(1 i.~ f) y
will "short circuit" to the first 1
and
({~ 1 i.~ f)
may be faster to get first coordinates than my original solution, though errors
if there are no items with 1 = f
On Friday, October 21, 2022 at 12:55:41 p.m. EDT, 'Pascal Jasmin' via
Programming <programm...@jsoftware.com> wrote:
}.^:(0 = f@{.)^:_
will return the list with the head being the first f not equal 0.
On Friday, October 21, 2022 at 12:19:41 p.m. EDT, Ed Gottsman
<edward.j.gotts...@gmail.com> wrote:
Hi. I’m blanking on something basic and research isn’t helping. When the
blindingly obvious solution is revealed I will blame a combination of sleep
deprivation and senescence.
I’ve got a long list of coordinates ordered by desirability. I want to invoke
f (a custom script) with each coordinate in turn. f may return 0 (failure), in
which case I want to invoke it again with the next coordinate. When f
(eventually) returns 1, I want to terminate—the remainder of the coordinates
should not be processed. (Note that the very first invocation of f may return
1.)
This *almost* feels like ^: in its Do While form. Almost. It also feels like
SCs around list operations (though they seem to be limited to primitives).
Help.
Many thanks.
Ed
Sent from my iPad
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