# [R] Puzzled over "partial"

Nick Wray n|ckmwr@y @end|ng |rom gm@||@com
Mon Jul 26 13:53:40 CEST 2021

```Hello   I am puzzled about the use or status of "partial" in R.  years ago
I found a little piece of code which gives the pth largest number in a
vector:
x<-c(5,4,7,2,6,9)
n <- length(x)
p<-4
sort(x,partial=n-(n-p))[n-(n-p)]
This works fine, although I have tried playing around with the code and
don't understand what "partial" is doing here.
However, wanted to work out what was going on, so I looked for "partial in
r" on t'internet and got this site:Partial apply a function, filling in
some arguments. — partial • purrr (tidyverse.org)
<https://purrr.tidyverse.org/reference/partial.html#:~:text=Source%3A%20R%2Fpartial.R%20Partial%20function%20application%20allows%20you%20to,that%20an%20argument%20can%20only%20be%20partialised%20once.>
Examples:
# Partial is designed to replace the use of anonymous functions for #
<https://purrr.tidyverse.org/reference/keep.html>(x, is.null) # we can
write: compact2 <- partial(discard, .p = is.null) # partial() works fine
with functions that do non-standard # evaluation my_long_variable <- 1:10
plot2 <- partial(plot, my_long_variable) plot2()
when i tried to run the examples on this site I got error messages - R
(studio) did not recognise the "partial" function here.  The site did not
say that I needed a particular package to run the "partial" function.
Are there essentially two different things in R both described as "partial"
but which are actually different entities?
Thanks for any elucidation
Nick Wray

[[alternative HTML version deleted]]

```