R help - Jul 2004 - ordering of levels.

Hi!
Have the following factors with the following levels.
 tmp$norm
 [1] rank rank rank rank rank log  log  log  rank sqrt sqrt sqrt log  log  rank
[16] rank rank sqrt sqrt sqrt sqrt log  log  log  log  sqrt none none none none
[31] none none none none sqrt none
Levels: log none rank sqrt

I would like to add an ordering to the levels.
none<sqrt<log<rank

I tried with 
tmp$norm <-factor(tmp$norm,labels =
c("none","sqrt","log","rank"),ordered=T)
>tmp$norm
 [1] log  log  log  log  log  none none none log  rank rank rank none none log 
[16] log  log  rank rank rank rank none none none none rank sqrt sqrt sqrt sqrt
[31] sqrt sqrt sqrt sqrt rank sqrt
Levels: none < sqrt < log < rank

But this is not what I would like to have because the command not only
superimposes an ordering but also changes the factors!

Eryk

Wolski wrote:
> Hi!
> Have the following factors with the following levels.
>  tmp$norm
>  [1] rank rank rank rank rank log  log  log  rank sqrt sqrt sqrt log  log 
rank
> [16] rank rank sqrt sqrt sqrt sqrt log  log  log  log  sqrt none none none
none
> [31] none none none none sqrt none
> Levels: log none rank sqrt
> 
> I would like to add an ordering to the levels.
> none<sqrt<log<rank
> 
> I tried with 
> tmp$norm <-factor(tmp$norm,labels =
c("none","sqrt","log","rank"),ordered=T)
> 
>>tmp$norm
> 
>  [1] log  log  log  log  log  none none none log  rank rank rank none none
log
> [16] log  log  rank rank rank rank none none none none rank sqrt sqrt sqrt
sqrt
> [31] sqrt sqrt sqrt sqrt rank sqrt
> Levels: none < sqrt < log < rank
> 
> But this is not what I would like to have because the command not only
superimposes an ordering but also changes the factors!
> 
> Eryk
> 
Eryk,
   See ?factor or ?ordered which will help. I think what you want is:

lev <- c("none", "sqrt", "log",
"rank")
tmp$norm <- ordered(tmp$norm, levels = lev)

or

tmp$norm <- factor(tmp$norm, levels = lev, ordered = TRUE)

Note the use of "levels" and not "labels".

--sundar