R help - Nov 2011 - passing dataframe col name through cbind()

Hi all ---

I note that the column name of the first column in a dataframe does not
necessarily get passed on when using cbind (example below)?

I'm looking for help in clarifying why this behavior occurs, and how I can
get all col names, including the first, passed on to the result?while I suspect
it's obvious and documented to the cognoscenti, it's puzzling me?

Many thanks for any help on this...
Eric
> scores <-
data.frame(name=c("Bob","Ron","Bud"),round1=c(40,30,20),round2=c(5,6,4))
#some toy data
>
> scores
  name round1 round2
1  Bob     40      5
2  Ron     30      6
3  Bud     20      4
>
> cbind(scores[,1],total=rowSums(scores[,2:3]),scores[,2:3])
  scores[, 1] total round1 round2
1         Bob    45     40      5
2         Ron    36     30      6
3         Bud    24     20      4
> 
...first column renamed...

?yet this passes all column names:
> cbind(scores[,1:3])
  name round1 round2
1  Bob     40      5
2  Ron     30      6
3  Bud     20      4
> 
?but this doesn't:
> cbind(scores[,1],scores[,2:3])
  scores[, 1] round1 round2
1         Bob     40      5
2         Ron     30      6
3         Bud     20      4


--
 Eric Rupley
 University of Michigan, Museum of Anthropology
 1109 Geddes Ave, Rm. 4013
 Ann Arbor, MI 48109-1079
 
 erupley at umich.edu
 +1.734.276.8572

Try this:
> cbind(scores[,1,drop = FALSE], scores[,2:3])
  name round1 round2
1  Bob     40      5
2  Ron     30      6
3  Bud     20      4
>
Then do ?'[' to learn about 'drop'

On Tue, Nov 8, 2011 at 1:06 PM, Eric Rupley <erupley at umich.edu>
wrote:
>
>
>
> Hi all ---
>
> I note that the column name of the first column in a dataframe does not
necessarily get passed on when using cbind (example below)?
>
> I'm looking for help in clarifying why this behavior occurs, and how I
can get all col names, including the first, passed on to the result?while I
suspect it's obvious and documented to the cognoscenti, it's puzzling
me?
>
> Many thanks for any help on this...
> Eric
>
>> scores <-
data.frame(name=c("Bob","Ron","Bud"),round1=c(40,30,20),round2=c(5,6,4))
#some toy data
>>
>> scores
> ?name round1 round2
> 1 ?Bob ? ? 40 ? ? ?5
> 2 ?Ron ? ? 30 ? ? ?6
> 3 ?Bud ? ? 20 ? ? ?4
>>
>
>> cbind(scores[,1],total=rowSums(scores[,2:3]),scores[,2:3])
> ?scores[, 1] total round1 round2
> 1 ? ? ? ? Bob ? ?45 ? ? 40 ? ? ?5
> 2 ? ? ? ? Ron ? ?36 ? ? 30 ? ? ?6
> 3 ? ? ? ? Bud ? ?24 ? ? 20 ? ? ?4
>>
>
> ...first column renamed...
>
> ?yet this passes all column names:
>
>> cbind(scores[,1:3])
> ?name round1 round2
> 1 ?Bob ? ? 40 ? ? ?5
> 2 ?Ron ? ? 30 ? ? ?6
> 3 ?Bud ? ? 20 ? ? ?4
>>
>
> ?but this doesn't:
>
>> cbind(scores[,1],scores[,2:3])
> ?scores[, 1] round1 round2
> 1 ? ? ? ? Bob ? ? 40 ? ? ?5
> 2 ? ? ? ? Ron ? ? 30 ? ? ?6
> 3 ? ? ? ? Bud ? ? 20 ? ? ?4
>
>
> --
> ?Eric Rupley
> ?University of Michigan, Museum of Anthropology
> ?1109 Geddes Ave, Rm. 4013
> ?Ann Arbor, MI 48109-1079
>
> ?erupley at umich.edu
> ?+1.734.276.8572
> ______________________________________________
> R-help at r-project.org mailing list
> 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.
>


-- 
Jim Holtman
Data Munger Guru

What is the problem that you are trying to solve?
Tell me what you want to do, not how you want to do it.