Oops, you are correct, I should have done an outer-product difference there.

Thanks for pointing this out,

-- 
Raul

On Thu, Nov 14, 2019 at 8:34 PM Ben Gorte <[email protected]> wrote:
>
> As to intuition, I started wondering whether your sentences produce
> averages of distances between two random points, or between the origin and
> a random point (=vector length). Or whether that might be the same (?)
> For two points at a time I get:
>
> avg %: +/ *: -/?2 1000 1000$0
>
> 12.8989
>
> avg %: +/ *: -/?2 4000 1000$0
>
> 25.8177
>
> avg %: +/ *: -/?2 10000 1000$0
>
> 40.8296
>
> (if I'm not mistaken)
>
>
> So it is not the same. In 1D it's 0.33 vs. 0.5 and that ratio seems to hold
> in any dimension (which makes sense. Intuitively).
>
>
> Greetings,
>
> Ben
>
>
>
>
>
> On Fri, 15 Nov 2019 at 03:47, Raul Miller <[email protected]> wrote:
>
> > For example, here's an illustration of the concept that the average
> > distance between random points in a unit hypercube increases with the
> > number of dimensions:
> >
> >    (+/%#)+/&.:*:?1000 1000$0
> > 18.2652
> >    (+/%#)+/&.:*:?4000 1000$0
> > 36.5102
> >    (+/%#)+/&.:*:?10000 1000$0
> > 57.7314
> >
> > Thanks,
> >
> > --
> > Raul
> >
> > On Thu, Nov 14, 2019 at 11:16 AM Raul Miller <[email protected]>
> > wrote:
> > >
> > > I stumbled across this today:
> > > https://github.com/leopd/geometric-intuition accompanied by an
> > > assertion that you can find the eigenvectors for a hermitian matrix
> > > from its eigenvalues and the eigenvalues of its submatrices.  I have
> > > not yet worked through the details of that, but it sounds plausible
> > > and might be of interest to some of you, here.
> > >
> > > But the repository itself covers a lot more ground  than that.
> > >
> > > Anyways, the code is python, but a lot of it is fairly straightforward
> > > to re-implement, and there's good english descriptions and
> > > illustrations, also. So this looks like fun.
> > >
> > > FYI,
> > > --
> > > Raul
> > ----------------------------------------------------------------------
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> >
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