#factor_function
فرم کلی این تابع به صورت :
factor(x = character(), levels, labels = levels,
exclude = NA, ordered = is.ordered(x))

که از یک رشته شی محتويات انها را خارج و در
Levels
قرار میدهد و میتوان به انها برچسب نیز نسبت داد ، و ordered ترتیب را برای ما مشخص میکند

> mons = c("March","April","January","November","January",
+ "September","October","September","November","August",
+ "January","November","November","February","May","August",
+ "July","December","August","August","September","November",
+ "February","April")
> mons = factor(mons)
> table(mons)
mons
    April    August  December  February   January      July
        2         4         1         2         3         1
    March       May  November   October September
        1         1         5         1         3

ordered=TRUE

ترتیب اعضای فاکتور را مشخص میکند

> fert = c(10,20,20,50,10,20,10,50,20)
> fert = factor(fert,levels=c(10,20,50),ordered=TRUE)
> fert
[1] 10 20 20 50 10 20 10 50 20
Levels: 10 < 20 < 50

@R_Experts