[R] How to dynamically add variables to a dataframe

Ista Zahn |@t@z@hn @end|ng |rom gm@||@com
Mon Apr 23 20:48:31 CEST 2018


Another option is

d0[paste0("V", 1:nrow(d1))] <- 0

--Ista

On Sun, Apr 22, 2018 at 4:23 AM, Eric Berger <ericjberger using gmail.com> wrote:
> Hi Luca,
> How about this?
>
> # create some dummy data since I don't have your d0 or d1
>> n  <- 3
>> d0 <- data.frame(a=runif(5),b=runif(5))
>
> # here's the suggested code
>> d1 <- cbind(d0, matrix(0,nrow(d0),n))
>> colnames(d1)[1:n + ncol(d0)] <- paste("V",1:n,sep="")
>
> HTH,
> Eric
>
>
> On Sun, Apr 22, 2018 at 11:13 AM, Luca Meyer <lucam1968 using gmail.com> wrote:
>
>> Hi,
>>
>> I am a bit rusty with R programming and do not seem to find a solution to
>> add a number of variables to my existing dataframe. Basically I need to add
>> n=dim(d1)[1] variables to my d0 dataframe and I would like them to be named
>> V1, V2, V3, ... , V[dim(d1)[1])
>>
>> When running the following code:
>>
>> for (t in 1:dim(d1)[1]){
>>   d0$V[t] <- 0
>> }
>>
>> all I get is a V variable populated with zeros...
>>
>> I am sure there is a fairly straightforward code to accomplish what I need,
>> any suggestion?
>>
>> Thank you,
>>
>> Luca
>>
>>         [[alternative HTML version deleted]]
>>
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>>
>
>         [[alternative HTML version deleted]]
>
> ______________________________________________
> R-help using 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.




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