Yuan Chun Ding
2021-Jul-02 22:42 UTC
[R] add a variable a data frame to sequentially count unique rows
Hi Jeff, Thank you for your quick response!! I made this following summary file, however, I want to add the count number sequentially into the original file, because I have several more columns to explain or annotate the first two columns. count_test <- test %>% group_by(group1 ) %>%summarise(Number_of_region = n_distinct(group2)) Ding -----Original Message----- From: Jeff Newmiller [mailto:jdnewmil at dcn.davis.ca.us] Sent: Friday, July 2, 2021 3:36 PM To: r-help at r-project.org; Yuan Chun Ding <ycding at coh.org>; r-help at r-project.org Subject: Re: [R] add a variable a data frame to sequentially count unique rows It is poor analytical design to keep duplicates. If they are not duplicates then there should be a distinguishing additional column. IMO you should re-think your analysis rather than accomplish this short-term goal only to find down the road that this duplication causes future problems. On July 2, 2021 3:27:21 PM PDT, Yuan Chun Ding <ycding at coh.org> wrote:>Hi R users, > >In this test file, >test <- data.frame(group1=c("g1", "g1", "g1", "g2", "g2", "g2", "g2", >"g2", "g2"), > group2=c("k1", "a2", "a2", "c5", "n6", "n6", "n6", "m10","m10"), > count= c( 1, 1, 2, 1, 2, 2, 2, 3, 3 )); > >I have group 1 and group2 variable and want to add the count variable >to sequentially count unique rows defined by group1 and group2. > >I hope to use the following functions in library (tidyverse), No one >worked well. >test %>% group_by(group1, group2) %>% mutate(count = row_number()) test >%>% group_by(group1, group2) %>% mutate(count = 1:n()) test %>% >group_by(group1, group2) %>% mutate(count = seq_len(n())) test %>% >group_by(group1, group2) %>% mutate(count = seq_along(group1, >group2)) > >Can you help me to make the third column in the test data frame? > >Thank you, > >Ding > >---------------------------------------------------------------------- >------------------------------------------------------------ >-SECURITY/CONFIDENTIALITY WARNING- > >This message and any attachments are intended solely for the individual >or entity to which they are addressed. This communication may contain >information that is privileged, confidential, or exempt from disclosure >under applicable law (e.g., personal health information, research data, >financial information). Because this e-mail has been sent without >encryption, individuals other than the intended recipient may be able >to view the information, forward it to others or tamper with the >information without the knowledge or consent of the sender. If you are >not the intended recipient, or the employee or person responsible for >delivering the message to the intended recipient, any dissemination, >distribution or copying of the communication is strictly prohibited. If >you received the communication in error, please notify the sender >immediately by replying to this message and deleting the message and >any accompanying files from your system. If, due to the security risks, >you do not wish to receive further communications via e-mail, please >reply to this message and inform the sender that you do not wish to >receive further e-mail from the sender. (LCP301) > >______________________________________________ >R-help at r-project.org mailing list -- To UNSUBSCRIBE and more, see >https://urldefense.com/v3/__https://stat.ethz.ch/mailman/listinfo/r-hel >p__;!!Fou38LsQmgU!6hr10CQQybFHF0rsNtkWtEHa_9iV_iYS8khF0fy8MDanYoQM40_aN >bjXXLLn$ >PLEASE do read the posting guide >https://urldefense.com/v3/__http://www.R-project.org/posting-guide.html >__;!!Fou38LsQmgU!6hr10CQQybFHF0rsNtkWtEHa_9iV_iYS8khF0fy8MDanYoQM40_aNV >Lja7f2$ and provide commented, minimal, self-contained, reproducible >code.-- Sent from my phone. Please excuse my brevity.
Jeff Newmiller
2021-Jul-02 23:51 UTC
[R] add a variable a data frame to sequentially count unique rows
I am not sure I understand... you are referring to files but we are not
discussing files here. There are "input" and "output" phases
yet to be
dealt with that separate the analysis you do in R from the files
themselves. We are discussing data frames here.
Regardless, you either have duplicates in your input (faulty data) or you
do not have duplicates because there are additional distinguishing columns
that you have not identified. (https://en.wikipedia.org/wiki/Primary_key)
The solution to the problem that you should not have involves making a
sensible (not faulty) copy of your data, setting up the count column, and
then joining the faulty data with the sensible data.
Note that the ordering of the result happens to be retained when using
dplyr::left_join, but is not retained using most other join
implementations (such as base::merge). There can be significant
performance gains to be had by giving up on record ordering, which is one
of the reasons why having a valid primary key can be so important.
library(dplyr)
lookup_df <- ( test
%>% select( group1, group2 )
%>% filter( !duplicated( . ) )
%>% group_by( group1 )
%>% mutate( count1 = seq.int( n() ) )
%>% ungroup()
)
ans <- left_join( test, lookup_df, by = c( "group1",
"group2" ) )
On Fri, 2 Jul 2021, Yuan Chun Ding wrote:
> Hi Jeff,
>
> Thank you for your quick response!!
> I made this following summary file, however, I want to add the count number
sequentially into the original file, because I have several more columns to
explain or annotate the first two columns.
>
> count_test <- test %>% group_by(group1 )
%>%summarise(Number_of_region = n_distinct(group2))
>
>
> Ding
> -----Original Message-----
> From: Jeff Newmiller [mailto:jdnewmil at dcn.davis.ca.us]
> Sent: Friday, July 2, 2021 3:36 PM
> To: r-help at r-project.org; Yuan Chun Ding <ycding at coh.org>;
r-help at r-project.org
> Subject: Re: [R] add a variable a data frame to sequentially count unique
rows
>
> It is poor analytical design to keep duplicates. If they are not duplicates
then there should be a distinguishing additional column. IMO you should re-think
your analysis rather than accomplish this short-term goal only to find down the
road that this duplication causes future problems.
>
> On July 2, 2021 3:27:21 PM PDT, Yuan Chun Ding <ycding at coh.org>
wrote:
>> Hi R users,
>>
>> In this test file,
>> test <- data.frame(group1=c("g1", "g1",
"g1", "g2", "g2", "g2", "g2",
>> "g2", "g2"),
>> group2=c("k1", "a2", "a2",
"c5", "n6", "n6", "n6",
"m10","m10"),
>> count= c( 1, 1, 2, 1, 2, 2, 2, 3, 3 ));
>>
>> I have group 1 and group2 variable and want to add the count variable
>> to sequentially count unique rows defined by group1 and group2.
>>
>> I hope to use the following functions in library (tidyverse), No one
>> worked well.
>> test %>% group_by(group1, group2) %>% mutate(count =
row_number()) test
>> %>% group_by(group1, group2) %>% mutate(count = 1:n()) test
%>%
>> group_by(group1, group2) %>% mutate(count = seq_len(n())) test
%>%
>> group_by(group1, group2) %>% mutate(count = seq_along(group1,
>> group2))
>>
>> Can you help me to make the third column in the test data frame?
>>
>> Thank you,
>>
>> Ding
>>
>> ----------------------------------------------------------------------
>> ------------------------------------------------------------
>> -SECURITY/CONFIDENTIALITY WARNING-
>>
>> This message and any attachments are intended solely for the individual
>> or entity to which they are addressed. This communication may contain
>> information that is privileged, confidential, or exempt from disclosure
>> under applicable law (e.g., personal health information, research data,
>> financial information). Because this e-mail has been sent without
>> encryption, individuals other than the intended recipient may be able
>> to view the information, forward it to others or tamper with the
>> information without the knowledge or consent of the sender. If you are
>> not the intended recipient, or the employee or person responsible for
>> delivering the message to the intended recipient, any dissemination,
>> distribution or copying of the communication is strictly prohibited. If
>> you received the communication in error, please notify the sender
>> immediately by replying to this message and deleting the message and
>> any accompanying files from your system. If, due to the security risks,
>> you do not wish to receive further communications via e-mail, please
>> reply to this message and inform the sender that you do not wish to
>> receive further e-mail from the sender. (LCP301)
>>
>> ______________________________________________
>> R-help at r-project.org mailing list -- To UNSUBSCRIBE and more, see
>> https://urldefense.com/v3/__https://stat.ethz.ch/mailman/listinfo/r-hel
>> p__;!!Fou38LsQmgU!6hr10CQQybFHF0rsNtkWtEHa_9iV_iYS8khF0fy8MDanYoQM40_aN
>> bjXXLLn$
>> PLEASE do read the posting guide
>> https://urldefense.com/v3/__http://www.R-project.org/posting-guide.html
>> __;!!Fou38LsQmgU!6hr10CQQybFHF0rsNtkWtEHa_9iV_iYS8khF0fy8MDanYoQM40_aNV
>> Lja7f2$ and provide commented, minimal, self-contained, reproducible
>> code.
>
> --
> Sent from my phone. Please excuse my brevity.
>
---------------------------------------------------------------------------
Jeff Newmiller The ..... ..... Go Live...
DCN:<jdnewmil at dcn.davis.ca.us> Basics: ##.#. ##.#. Live
Go...
Live: OO#.. Dead: OO#.. Playing
Research Engineer (Solar/Batteries O.O#. #.O#. with
/Software/Embedded Controllers) .OO#. .OO#. rocks...1k