Another possible approach is to use split -> lapply -> rbind, which I
often find to be conceptually simpler:
d <- data.frame(Serial = c(1, 1, 2, 2, 2, 3, 3),
Measurement = c(17, 16, 12, 8, 10, 19, 13))
dlist <- split(d, d$Serial)
dlist <- lapply(dlist, within,
{
Serial_test <- if (all(Measurement <= 16)) "pass" else "fail"
Meas_test <- ifelse(Measurement <= 16, "pass", "fail")
})
do.call(rbind, dlist)
-Deepayan
On Sun, Mar 22, 2020 at 12:29 PM Rolf Turner <r.tur...@auckland.ac.nz> wrote:
>
>
> On 22/03/20 4:01 pm, Thomas Subia via R-help wrote:
>
> > Colleagues,
> >
> > Here is my dataset.
> >
> > Serial Measurement Meas_test Serial_test
> > 1 17 fail fail
> > 1 16 pass fail
> > 2 12 pass pass
> > 2 8 pass pass
> > 2 10 pass pass
> > 3 19 fail fail
> > 3 13 pass pass
> >
> > If a measurement is less than or equal to 16, then Meas_test is pass. Else
> > Meas_test is fail
> > This is easy to code.
> >
> > Serial_test is a pass, when all of the Meas_test are pass for a given
> > serial. Else Serial_test is a fail.
> > I'm at a loss to figure out how to do this in R.
> >
> > Some guidance would be appreciated.
>
> In future, please present your data using dput(); makes life much easier
> for those trying to help you. Your data are really the first two
> columns of what you presented --- the last two columns are your desired
> output.
>
> Let "X" be these first two columns. Define
>
> foo <- function (X) {
> a <- with(X,Measurement <= 16)
> a <- ifelse(a,"pass","fail")
> b <- with(X,tapply(Measurement,Serial,function(x){all(x<=16)}))
> i <- match(X$Serial,names(b))
> b <- ifelse(b[i],"pass","fail")
> data.frame(Meas_test=a,Serial_test=b)
> }
>
> foo(X) gives:
>
> > Meas_test Serial_test
> > 1 fail fail
> > 2 pass fail
> > 3 pass pass
> > 4 pass pass
> > 5 pass pass
> > 6 fail fail
> > 7 pass fail
>
> If you want input and output combined, as in the way that you presented
> your data use cbind(X,foo(X)).
>
> cheers,
>
> Rolf Turner
>
> --
> Honorary Research Fellow
> Department of Statistics
> University of Auckland
> Phone: +64-9-373-7599 ext. 88276
>
> ______________________________________________
> R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see
> https://stat.ethz.ch/mailman/listinfo/r-help
> PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
> and provide commented, minimal, self-contained, reproducible code.
______________________________________________
R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see
https://stat.ethz.ch/mailman/listinfo/r-help
PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
and provide commented, minimal, self-contained, reproducible code.
