Given that I cannot arbitrarily change the data to make "a" an integer, can I still use "a" as a grouping variable?

I tried melt(example, id = factor(a)) but it does not work either. Must this change from numeric values to factors be done before applying melt?

Thanks,

baptiste

On 25 Jul 2008, at 16:35, Dieter Menne wrote:



a <- as.numeric(1:10)

example <- list(data.frame(a=a, b=sin(a)), data.frame(a=a, b=cos(a)))

melt(example, id = a) # this does not use a as an id variable


This is the documented behavior: Only integers and factors are used for
grouping, but as.numeric is double, even if 1:10 looks like integers

a <- as.integer(1:10)
or simply

a <- 1:10

Dieter

______________________________________________
R-help@r-project.org mailing list
https://stat.ethz.ch/mailman/listinfo/r-help
PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
and provide commented, minimal, self-contained, reproducible code.

Reply via email to