[R] combine filter() and select()

[Chris Evans]

Inline

----- Original Message -----
> From: "Ivan Calandra" <calandra using rgzm.de>
> To: "R-help" <r-help using r-project.org>
> Sent: Wednesday, 19 August, 2020 16:56:32
> Subject: [R] combine filter() and select()

> Dear useRs,
> 
> I'm new to the tidyverse world and I need some help on basic things.
> 
> I have the following tibble:
> mytbl <- structure(list(files = c("a", "b", "c", "d", "e", "f"), prop =
> 1:6), row.names = c(NA, -6L), class = c("tbl_df", "tbl", "data.frame"))
> 
> I want to subset the rows with "a" in the column "files", and keep only
> that column.
> 
> So I did:
> myfile <- mytbl %>%
>  filter(grepl("a", files)) %>%
>  select(files)
> 
> It works, but I believe there must be an easier way to combine filter()
> and select(), right?

I would write 

mytbl %>%
  filter(grepl("a", files)) %>%
  select(files) -> myfile

as I like to keep a sort of "top to bottom and left to right" flow when writing in the tidyverse dialect of R but that's really not important.

Apart from that I think what you've done is "proper tidyverse". To me another difference between the dialects is that classical R often seems to put value on, and make it easy, to do things with incredible few characters.  I think the people who are brilliant at that sort of coding, and there are many on this list, that sort of coding is also easy to read.  I know that Chinese is easy to read if you grew up on it but to a bear of little brain like me, the much more verbose style of tidyverse repays typing time with readability when I come back to my code and, though I have little experience of this yet, when I read other poeple's code.

What did you think wasn't "easy" about what you wrote?

Very best (all),

Chris

> 
> Thank you!
> Ivan
> 
> --
> Dr. Ivan Calandra
> TraCEr, laboratory for Traceology and Controlled Experiments
> MONREPOS Archaeological Research Centre and
> Museum for Human Behavioural Evolution
> Schloss Monrepos
> 56567 Neuwied, Germany
> +49 (0) 2631 9772-243
> https://www.researchgate.net/profile/Ivan_Calandra
> 
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-- 
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Chris Evans <chris using psyctc.org> Visiting Professor, University of Sheffield <chris.evans using sheffield.ac.uk>
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