Oh no, it's not because I said so. As I said, it's because this particular
definition, the current definition, says so. If you think the definition
should be / could be something else, we can discuss it. Truth be told, I
don't understand how you can have keys that don't have corresponding data,
or data that don't have corresponding keys. Sounds like a completely
different computation than _key_.
_Key_ (the current definition) is cognate with the GROUP-BY statement in
SQL, the monadic = function in k, the generalized beta in the Connection
Machine.
On Sun, Oct 13, 2019 at 6:36 PM 'Jim Russell' via Programming <
programm...@jsoftware.com> wrote:
> And only you, Roger, well deserve the right to answer "Because I said so!"
> I was only considering the case of u=#, and remembering that #/. was
> described as in the i. family, and seeing that...
>
> Well never mind. Sorry.
>
>
> > On Oct 13, 2019, at 7:50 PM, Roger Hui <rogerhui.can...@gmail.com>
> wrote:
> >
> >
> >>
> >> why do the sizes of the x and y argument to Key need to match?
> >
> > Because the x u/. y key adverb is _defined_ so that
> >
> > - items of x specify keys for _corresponding_ items of y and
> > - u is applied to each collection of y having identical keys.
> >
> > You can argue that the definition should be something else, but it is not
> > debatable that if you are going to use u/. then items of x must have
> > corresponding items in y, that is, x and y must have the same number of
> > items, that is, {.$x must be the same as {.$y . x and y need not have
> the
> > same shape, but the leading element of their shapes must be the same.
> >
> >
> >
> >> On Sun, Oct 13, 2019 at 3:58 PM 'Jim Russell' via Programming <
> >> programm...@jsoftware.com> wrote:
> >>
> >> Rick: My ability to read tacit expressions is so poor that I overlooked
> >> the fact that the your quoted output did not come directly from the Key
> >> expression; silly me, I thought there was some form of the
> >> modifiers/arguments to Key that yielded the results of two inputs.
> >>
> >> (In contrast to your skill, it took be about a half a day to come up
> with
> >> the tacit dyad(?) mmjnn=:(; ,.) to glue together my trigram table and
> one
> >> result vector.)
> >>
> >> So I wonder if I dare ask again:
> >> why do the sizes of the x and y argument to Key need to
> >> match?
> >>
> >> (Thanks again for all the help!)
> >>
> >>>> On Oct 12, 2019, at 5:16 AM, Ric Sherlock <tikk...@gmail.com> wrote:
> >>>
> >>>>> Or to summarise by trigram:
> >>>>>
> >>>>> (~.@; trig);|: <: #/.~&> supertrig
> >>>>>
> >>>>> +---+---+
> >>>>>
> >>>>> |ggt|1 2|
> >>>>>
> >>>>> |gta|2 0|
> >>>>>
> >>>>> |taa|1 1|
> >>>>>
> >>>>> |aaa|2 0|
> >>
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> >>
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