[R] for loop in assigning column names

Luis Ridao Cruz Luisr at frs.fo
Wed Mar 21 16:14:16 CET 2007


R-help,

I have a data frame (df) and I want to add some columns whose names
should correspond to the "i" index in the loop below.

 for(i in 1:10)
 {
df$eval(paste("St", as.character(i), sep = "" ))  <- ObJeCt[i]
 }

An error message comes out : 

"Error: attempt to apply non-function"

How can I get around this?

I could do something like :

df$St2 <- NA
df$St3 <- NA
dft$St4 < -NA
..

and afterwards assign the results of the loop above 
to the columns df$St2,df$St3,,,,,,,,,,,

The problem is that my object "ObJeCt[i]" may change in size
and definition and therefore a way to systematize the task would
be desirable.

Thanks in advance

> version
               _                           
platform       i386-pc-mingw32             
arch           i386                        
os             mingw32                     
system         i386, mingw32               
status                                     
major          2                           
minor          4.1                         
year           2006                        
month          12                          
day            18                          
svn rev        40228                       
language       R                           
version.string R version 2.4.1 (2006-12-18)



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