[R] Find tibble row with maximum recorded value

[Bert Gunter]

Perhaps you meant to point this out, but the cfs[which.max(cfs)] and
cfs == ... are not the same:

> x <- rep(1:2,3)
> x
[1] 1 2 1 2 1 2
> x[which.max(x)]
[1] 2
> x[x==max(x)]
[1] 2 2 2

So maybe your point is: which does the OP want (in case there are
repeated maxes)? I suspect the == forms, but ...?

Bert Gunter

On Fri, Dec 3, 2021 at 2:56 PM Rui Barradas <ruipbarradas using sapo.pt> wrote:
>
> Hello,
>
> Inline.
>
> Às 22:08 de 03/12/21, Rich Shepard escreveu:
> > On Fri, 3 Dec 2021, Rich Shepard wrote:
> >
> >> I find solutions when the data_frame is grouped, but none when it's not.
> >
> > Thanks, Bert. ?which.max confirmed that's all I need to find the maximum
> > value.
> >
> > Now I need to read more than ?filter to learn why I'm not getting the
> > relevant row with:
> >> which.max(pdx_disc$cfs)
> > [1] 8054
>
> This is the *index* for which cfs is the first maximum, not the maximum
> value itself.
>
> >
> >> filter(pdx_disc, cfs == 8054)
>
> Therefore, you probably want any of
>
>
> filter(pdx_disc, cfs == cfs[8054])
>
> filter(pdx_disc, cfs == cfs[which.max(cfs)])
>
> filter(pdx_disc, cfs == max(cfs))    # I find this one better, simpler
>
>
> Hope this helps,
>
> Rui Barradas
>
>
> > # A tibble: 0 × 9
> > # … with 9 variables: site_nbr <chr>, year <int>, mon <int>, day <int>,
> > #   hr <dbl>, min <dbl>, tz <chr>, cfs <dbl>, sampdt <dttm>
> >
> > Regards,
> >
> > Rich
> >
> > ______________________________________________
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> ______________________________________________
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> and provide commented, minimal, self-contained, reproducible code.