[R] combine filter() and select()

[Ivan Calandra]

Dear Chris,

I didn't think about having the assignment at the end as you showed; it
indeed fits the pipe workflow better.

By "easy", I actually meant shorter. As you said, in base R, I usually
do that in 1 line, so I was hoping to do the same in tidyverse. But I'm
glad to hear that I'm using tidyverse the proper way :)

Best regards,
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

On 19/08/2020 19:21, Chris Evans wrote:
> 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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