R help - Oct 2011 - Add col in data.frame

Hello Gurus,
                I am still new to R. Here is my issue.
I was trying to add column to data frame that was populated by read.spss().
When I used cbind to add a new variable(column).

library(foreign)
mydf<-read.spss(file="C:/myspss.sav",use.value.labels=FALSE,
to.data.frame=TRUE,use.missings=FALSE)
attr(mydf,"variable.labels")
## it gives you all the labels

##Adding a new variable(col) to mydf
newcolm <- list(frt="grapes")
mydf <- cbind(mydf, newrow)

##Now checking to see labels again
attr(mydf,"variable.labels")

## And you get NULL

Can anyone please help me to achieve this without loosing any default
attribute that was there?

Thanks and Regards
-- 
SmartG

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On 10/29/2011 06:54 PM, Smart Guy wrote:
> Hello Gurus,
>                  I am still new to R. Here is my issue.
> I was trying to add column to data frame that was populated by read.spss().
> When I used cbind to add a new variable(column).
>
> library(foreign)
> mydf<-read.spss(file="C:/myspss.sav",use.value.labels=FALSE,
> to.data.frame=TRUE,use.missings=FALSE)
> attr(mydf,"variable.labels")
> ## it gives you all the labels
>
> ##Adding a new variable(col) to mydf
> newcolm<- list(frt="grapes")
> mydf<- cbind(mydf, newrow)
>
> ##Now checking to see labels again
> attr(mydf,"variable.labels")
>
> ## And you get NULL
>
> Can anyone please help me to achieve this without loosing any default
> attribute that was there?
Hi SmartG,
I assume that the "newcolm"-"newrow" is just a typo in the
example
above. Assuming that you are managing to get your new column in
"mydf",
you can add the new variable name like this:

oldvl<-attr(mydf,"variable.labels")
mydf<-cbind(mydf,newrow)
attr(mydf,"variable.labels")<-c(oldvl,"newvar")

Jim