Dear R-listers,
I am trying to assign colnames to a data frame within a loop, but I keep
getting a "target of assignment expands to non-language object"-error. I
need to split up a large dataset into about 20 smaller ones, and I would
like to assign colnames within the loop, so I won't have to type the
same thing 20 times over.
I have concocted this really goofy example which constructs two
datasets:
-----
male <- rep(0:1, each=5)
age <- factor(c(10:14,10:14))
DF <- data.frame(male, age, res1=rnorm(10), res2=rnorm(10),
res3=rnorm(10))
for(n in 0:1) {
assign(paste("test",n, sep="."), as.data.frame(t(subset(DF,
male==n, select=c(res1, res2, res3)))))
colnames(get(paste("test",n, sep="."))) <-
paste("age",levels(age), "m", n, sep="") # This line gives an error.
assign(colnames(paste("test",n, sep="."))) <-
paste("age",levels(age), "m", n, sep="") # This line gives the same
error.
}
-------
The following command assigns the right colnames to the 'test.0' data
frame, but I want this line inside the loop so I won't have to type it
20 times over.
colnames(test.0) <- paste("age",levels(age), "m", 0, sep="")
Thank you in advance for any assistance.
Peter.
R version 2.8.1 (2008-12-22)
i386-pc-mingw32
locale:
LC_COLLATE=Danish_Denmark.1252;LC_CTYPE=Danish_Denmark.1252;LC_MONETARY=
Danish_Denmark.1252;LC_NUMERIC=C;LC_TIME=Danish_Denmark.1252
attached base packages:
[1] tools stats graphics grDevices utils datasets methods
base
other attached packages:
[1] epiR_0.9-14 maptools_0.7-18 sp_0.9-29 foreign_0.8-30
chron_2.3-28
loaded via a namespace (and not attached):
[1] grid_2.8.1 lattice_0.17-20