Here's a tentative implementation of part of what I think you have described:
commute=:3 :0
assert.2=#$y
assert.=/$y
assert. 0={.u b. 0
mask=. <:/~i.#y
inds=. (>. |:)mask*i.$y
inds{u mask #&, y
)
That said, I don't think this would work for you - this winds up
testing each item independently so there's no comparison involved.
Perhaps you could flesh out an example to better show what you mean?
Thanks,
--
Raul
On Fri, Jun 29, 2018 at 12:04 PM David Lambert <[email protected]> wrote:
>
> I have an equality test. If a=b then b=a . (In my case "find overlapping
> spheres", in other words the equality test may be non-trivial.) The new
> adverb would compute only the upper triangular set of cases and thereby
> save about half the time.
>
> NB. assuming the main diagonal could be interesting
> NB. the new adverb would compute these cases
> <:/~ i.7
> 1 1 1 1 1 1 1
> 0 1 1 1 1 1 1
> 0 0 1 1 1 1 1
> 0 0 0 1 1 1 1
> 0 0 0 0 1 1 1
> 0 0 0 0 0 1 1
> 0 0 0 0 0 0 1
> ----------------------------------------------------------------------
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