R help - Aug 2001 - Pulling columns out of a data.frame

Hi there

Probably a very simple solution to this problem.

I have a character vector eg
c("name1","name2","name3") and I want to pull
out these columns from a data.frame, converting each of these columns into
factors also.

Many thanks

Rachel

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To pull out a column, say myColumn, you can do something like:
  myColumn["name1"]
or
  myColumn[c("name1", "name2")]

To convert to factor I believe you can use the factor() command.

Cheers,

Kevin
> 
> From: "Rachel Cunliffe" <rachel at stat.auckland.ac.nz>
> Date: Fri, 10 Aug 2001 11:06:42 +1200
> To: "[R]" <r-help at stat.math.ethz.ch>
> Subject: [R] Pulling columns out of a data.frame
> 
> Hi there
> 
> Probably a very simple solution to this problem.
> 
> I have a character vector eg
c("name1","name2","name3") and I want to pull
> out these columns from a data.frame, converting each of these columns into
> factors also.
> 
> Many thanks
> 
> Rachel
> 
>
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> r-help mailing list -- Read http://www.ci.tuwien.ac.at/~hornik/R/R-FAQ.html
> Send "info", "help", or "[un]subscribe"
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>
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> 
-----------------------------------
Ko-Kang Kevin Wang
Statistical Analysis Division Leader
Software Developers' Klub (SDK)
University of Auckland
New Zealand

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Rachel Cunliffe wrote:
>
> ...I have a character vector eg
c("name1","name2","name3") and I want to pull
> out these columns from a data.frame, converting each of these columns into
> factors also.
Assuming that the column in your data.frame is named "names", and the
data frame is named "mydat",

new.names<-as.factor(mydat["names"])

should give you the column of name types as a factor vector.

Jim
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