[R] Dataframes and text identifier columns

[Richard M. Heiberger]

please stay on list.  I am returning this to the list.

David's comment that b is never used might be relevant.
I think the next step is for you to post a small dataset that causes the problem
dput(head(Inp_dat))
might be enough.

Rich

On Sun, Jun 29, 2014 at 3:11 PM, Brian Willis <b.h.willis at bham.ac.uk> wrote:
> Hi
>
> This does not work either. Comes up with same result
>
> Regards
>
> Brian
>
> ******************************
>
> Dr Brian H Willis
> NIHR Clinical Lecturer
> Primary Care Clinical Sciences
> University of Birmingham
> Edgbaston
> Birmingham. B15 2TT
> tel +44 121 414 7979
> b.h.willis at bham.ac.uk
> http://www.birmingham.ac.uk/brian-willis
>
> ________________________________________
> From: Richard M. Heiberger [rmh at temple.edu]
> Sent: 29 June 2014 18:34
> To: Brian Willis
> Cc: r-help
> Subject: Re: [R] Dataframes and text identifier columns
>
> Inp_dat<- read.csv("/File/Input data.csv")
> out_put[i,]<-data.frame(Case, stdL, stdPP, stdSE, L, PP, PP_SE)
>
> These two statements look like the source of the problem.
> Add the optional argument
>      stringsAsFactors=FALSE
> to both.
> Rich
>
> On Sun, Jun 29, 2014 at 8:46 AM, Brian Willis <b.h.willis at bham.ac.uk> wrote:
>> I am trying to incrementally add rows to an empty data frame. The data has 7
>> columns, the last 6 are numeric.
>>
>> For the first columns I would like to include a text identifier, called
>> ‘Case’ like Andrew, Burt, Charlie etc. that is also output to a data frame –
>> this is where I am having the problem
>>
>> The identifiers are being input from file which automatically assigns them
>> to a data frame
>> Code:
>>
>> Inp_dat<- read.csv("/File/Input data.csv")
>>
>> out_put<-data.frame(Case=character(), StdL=numeric(), StdPP=numeric(),
>> StdSE=numeric(), L=numeric(), MRPP=numeric(), MRSE=numeric(),
>> stringsAsFactors=FALSE)
>>
>> for(i in 1:4)
>> {
>> if (i==1) b<-Andrew
>> if (i==2) b<-Burt
>> if (i==3) b<-Charlie
>> if (i==4) b<-Dave
>>
>> pr <- Inp_dat$p[i]
>> SE_pr <- Inp_dat$SE[i]
>> r<- Inp_dat$r[i]
>> n<- Inp_dat$n[i]
>> Case<- levels(Inp_dat$Case)[i])
>> …
>>
>> out_put[i,]<-data.frame(Case, stdL, stdPP, stdSE, L, PP, PP_SE)
>>
>> }
>> out_put
>>
>>   Case     StdL          StdPP           StdSE           L
>> MRPP            MRSE
>> 1    1  19.466823   0.16432300   0.03137456   26.002294   0.2080145
>> 0.03804692
>> 2    1   2.334130    0.22566939   0.08962662    5.095703    0.3888451
>> 0.08399101
>> 3    1   2.588678    0.05502765   0.00454159   42.058326   0.4861511
>> 0.02128030
>> 4    1   7.857898    0.18457822   0.04372297    4.705487    0.1193687
>> 0.01921609
>>
>>
>> Unfortunately the Case column loses the labels Andrew, Burt …
>>
>> I’ve tried always to keep these, but are clearly doing something wrong. Can
>> anyone help?
>>
>>
>>
>>
>> --
>> View this message in context: http://r.789695.n4.nabble.com/Dataframes-and-text-identifier-columns-tp4693184.html
>> Sent from the R help mailing list archive at Nabble.com.
>>
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