[R] conversion of a list element to a vector
    Sundar Dorai-Raj 
    sundar.dorai-raj at pdf.com
       
    Tue May 20 13:47:15 CEST 2003
    
    
  
Philippe Hupé wrote:
> Hello,
> 
> I would like to extract unique elements of a variable which belongs to a 
> list
> 
> liste <- list(V1=c(1,2,3,5,2), V2=c(1,2,3,4,5))
> var <- "V1"
> uni <- unique(liste[var]) #does not work
> 
Need to use "[[" here. liste[var] is still a list. liste[[var]] is a 
vector. I would avoid using "var" as a variable name since it is also 
the function for computing the variance.
> I know that liste[var]$V1 works but for my problem, the label variable 
> "V1" is only know through the var variable.
> 
> I can I do
> 
> Thanks in advance.
> 
lapply(liste, unique) returns a list of length(liste) containing the 
unique values of each element in the list.
Regards,
Sundar
    
    
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