For example:
A=: 2 3 1 2 1,: 2 1 2 3 1
2 1 |.("_1) A
1 2 1 2 3
1 2 3 1 2
2 4 |.("_1) A
1 2 1 2 3
1 2 1 2 3
Thanks,
--
Raul
On Sat, May 16, 2020 at 9:11 PM Roger Hui <[email protected]> wrote:
>
> The question is, do you get a unique key (signature) if you rotate a row so
> that the first occurrence of the minimum value is first? I thought the
> answer was yes after thinking about it for a minute. I could be wrong.
>
>
> On Sat, May 16, 2020 at 5:53 PM Raul Miller <[email protected]> wrote:
>
> > A critical question here is whether the minimum value can appear more
> > than once in each row, or whether the examples (where each value is
> > has a unique appearance in each row) are adequately complex.
> >
> > Thanks,
> >
> > --
> > Raul
> >
> > On Sat, May 16, 2020 at 8:15 PM Roger Hui <[email protected]>
> > wrote:
> > >
> > > Hmm, you just want the keys: rotate each row so that the minimum item is
> > > first.
> > >
> > > (n i."_1 <./"1 n)|."_1 n
> > > 1 3 2 4
> > > 1 2 3 4
> > > 1 2 3 4
> > > 1 3 2 4
> > > 1 3 2 4
> > > 1 2 3 4
> > > 1 2 3 4
> > > 1 3 2 4
> > >
> > >
> > > On Sat, May 16, 2020 at 5:11 PM Roger Hui <[email protected]>
> > wrote:
> > >
> > > > ((n i."_1 <./"1 n)|."_1 n) </. n
> > > > ┌───────┬───────┐
> > > > │2 4 1 3│2 3 4 1│
> > > > │3 2 4 1│3 4 1 2│
> > > > │1 3 2 4│4 1 2 3│
> > > > │4 1 3 2│1 2 3 4│
> > > > └───────┴───────┘
> > > >
> > > > Rotate each row so that the minimum item is first, then use those
> > rotated
> > > > rows as keys.
> > > >
> > > >
> > > > On Sat, May 16, 2020 at 4:44 PM Skip Cave <[email protected]>
> > wrote:
> > > >
> > > >> I have run across this issue a few times in the past.
> > > >> The following 8x4 array has several rows that are 'rotational
> > duplicates'.
> > > >>
> > > >> ]n=.8 4$2 4 1 3 2 3 4 1 3 4 1 2 3 2 4 1 1 3 2 4 4 1 2 3 1 2 3 4 4 1 3
> > 2
> > > >>
> > > >> 2 4 1 3
> > > >>
> > > >> 2 3 4 1
> > > >>
> > > >> 3 4 1 2
> > > >>
> > > >> 3 2 4 1
> > > >>
> > > >> 1 3 2 4
> > > >>
> > > >> 4 1 2 3
> > > >>
> > > >> 1 2 3 4
> > > >>
> > > >> 4 1 3 2
> > > >>
> > > >>
> > > >> Is it possible to develop a verb that would find the rows that are
> > > >> rotational duplicates of each other. That is, find all the rows that
> > would
> > > >> be the same, if each row was rotated some integer value in the first
> > > >> dimension. The output of the verb would be the same shape array, but
> > with
> > > >> each duplicate row rotated such that they show as identical. Picking
> > the
> > > >> 'standard' rotation for a set of rotational duplicates is up to the
> > > >> implementer.
> > > >>
> > > >>
> > > >> Skip
> > > >> ----------------------------------------------------------------------
> > > >> For information about J forums see
> > http://www.jsoftware.com/forums.htm
> > > >>
> > > >
> > > ----------------------------------------------------------------------
> > > For information about J forums see http://www.jsoftware.com/forums.htm
> > ----------------------------------------------------------------------
> > For information about J forums see http://www.jsoftware.com/forums.htm
> >
> ----------------------------------------------------------------------
> For information about J forums see http://www.jsoftware.com/forums.htm
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