[R] trying to find the multiple combinations...

[Bert Gunter]

Are x,y, and z supposed to be positive whole numbers? If so, there may be
no solutions. If there is a solution set, of course any multiple of the set
is a solution set, so presumably you want a minimal set in some sense. This
strikes me as a hard problem mathematically, but maybe there is some
obvious way to set an upper bound on a minimal x,y, and z, in which case a
simple grid search could then be used.

Naturally, if any real numbers are sought, Jeff is correct.

Cheers,
Bert



Bert Gunter

"The trouble with having an open mind is that people keep coming along and
sticking things into it."
-- Opus (aka Berkeley Breathed in his "Bloom County" comic strip )

On Fri, Dec 8, 2017 at 12:19 AM, Jeff Newmiller <jdnewmil at dcn.davis.ca.us>
wrote:

> Solve for one of your variables and it will be given in terms of the other
> two. That is, there is a whole infinite plane of solutions. No, aggregate
> will not be sufficient to enumerate the solution set..
> --
> Sent from my phone. Please excuse my brevity.
>
> On December 7, 2017 10:37:37 PM PST, Benjamin Sabatini <
> sunscape1 at hotmail.com> wrote:
> >Hi,
> >
> >I'm trying to find a way to determine what multiples of the combination
> >of three or more numbers equals a forth number.
> >
> >So, if I had a number set like:
> >
> >c(13.4689, 12.85212, 17.05071)
> >
> >What combination and multiples of these numbers would average to
> >15.0078? (so, something that would tell me x, y, and z in (x*13.4689 +
> >y*12.85212+ z*17.05071) / x+y+z) = 15.0078
> >
> >I think this is doable with aggregate?
> >
> >       [[alternative HTML version deleted]]
>
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