[R] Replacing a few variable values within a DataFrame...

[baptiste auguie]

On 23 Mar 2009, at 17:39, Jason Rupert wrote:

>
> I would like to replace a few varaibles within a data frame.
>
> For example, in the dataframe below (contrived) I would like to  
> replace the current housesize value only if the Location is HSV.    
> However, I would like to leave the other values intact.
>

How about,

test_data2_df[test_data2_df$Location=="HSV", ] # these are the values  
to change

test_data2_df$housesize[test_data2_df$Location=="HSV"]  <- 28.3 # or  
whatever values


HTH,

baptiste

>
> I tried "ifelse", but I don't really need the else condition.
>
> test_data2_df<-data.frame(Variables=c("SQR Footage","SQR  
> Footage","SQR Footage","SQR Footage","SQR Footage","SQR  
> Footage","SQR Footage","SQR Footage","SQR Footage","SQR  
> Footage","SQR Footage","SQR Footage","SQR Footage","SQR  
> Footage","SQR Footage"),HouseSize=c(10, 20, 30, 40, 50, 15, 25, 35,  
> 45, 55, 18, 28, 38, 48, 58), Lot=c(1, 2, 3, 4, 5, 10, 20, 30, 40,  
> 50, 11, 21, 31, 41, 51), Location=c("HSV", "ATH", "HSV", "ATH", "FLO",
>                                     "HSV", "ATH", "HSV", "ATH", "FLO",
>                                     "HSV", "ATH", "HSV", "ATH",  
> "FLO"))
>
> Moreover, I want to preserve the rest of the values within the  
> data.  I thought some combination using the subset would get me  
> there, but I ended up with a long and ungangly looking code.
>
> Thanks for any help that is offered.
>
> ______________________________________________
> 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.

_____________________________

Baptiste Auguié

School of Physics
University of Exeter
Stocker Road,
Exeter, Devon,
EX4 4QL, UK

Phone: +44 1392 264187

http://newton.ex.ac.uk/research/emag