[R] Assign factor and levels inside function

Tim Howard tghoward at gw.dec.state.ny.us
Wed Apr 20 21:05:35 CEST 2005


R-help,
  After cogitating for a while, I finally figured out how to define a
data.frame column as factor and assign the levels within a function...
BUT I still need to pass the data.frame and its name separately. I can't
seem to find any other way to pass the name of the data.frame, rather
than the data.frame itself.  Any suggestions on how to go about it?  Is
there something like value(object) or name(object) that I can't find?

#sample dataframe for this example
y <- data.frame(
 one=c(1,1,3,3,5,7),
 two=c(2,2,6,6,8,8))

> levels(y$one)   # check out levels
NULL

# the function I've come up with
fncFact <- function(datfra, datfraNm){
datfra$one <- factor(datfra$one, levels=c(1,3,5,7,9))
assign(datfraNm, datfra, pos=1)
}

>fncFact(y, "y")
> levels(y$one)
[1] "1" "3" "5" "7" "9"

I suppose only for aesthetics and simplicity, I'd like to have only
pass the data.frame and get the same result.
Thanks in advance,
Tim Howard


> version
         _              
platform i386-pc-mingw32
arch     i386           
os       mingw32        
system   i386, mingw32  
status                  
major    2              
minor    0.1            
year     2004           
month    11             
day      15             
language R




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