Label variables

[CRV0503]

When i try and label my variables the following error message comes up

library(Hmisc)
label(nesarc.sub$S2AQ2) <- "Drank at least 12 alcoholic drinks in last 12 months" 

Error in attr(x, "label") <- value: attempt to set an attribute on NULL

confused where I'm setting the attribute on NULL.
If anyone has suggestions let me know thanks.

[alanarnholt]

We have no idea what is in your nesarc.sub data frame without providing a reproducible example....Using the NESARC data frame works fine:

library(PDS)
library(Hmisc)
label(NESARC$S2AQ2) <- "Drank at least 12 alcoholic drinks in last 12 months" 
head(NESARC$S2AQ2)
Drank at least 12 alcoholic drinks in last 12 months 
[1] 2 2 2 2 2 2
Levels: 1 2 9