Specify factor levels for intervals

Question

I have a continuous variable that I would like to turn into a factor.

The data is:

DCA<-c(0.14,0.14,0.16,0.16,0.27,0.27,0.07,0.07,0.41,0.41,0.00,0.00         


        

Answer 1

Look into cut:

cut(DCA, c(-Inf, seq(0, .5, .1), Inf))
#  [1] (0.1,0.2]  (0.1,0.2]  (0.1,0.2]  (0.1,0.2]  (0.2,0.3]  (0.2,0.3]  (0,0.1]   
#  [8] (0,0.1]    (0.4,0.5]  (0.4,0.5]  (-Inf,0]   (-Inf,0]   (0.3,0.4]  (0.3,0.4] 
# [15] (0.1,0.2]  (0.1,0.2]  (0.5, Inf] (0.5, Inf] (0.2,0.3]  (0.2,0.3]  (0,0.1]   
# [22] (0,0.1]    (0.4,0.5]  (0.4,0.5]  (0.2,0.3]  (0.2,0.3]  (0,0.1]    (0,0.1]   
# [29] (-Inf,0]   (-Inf,0]   (0.5, Inf] (0.5, Inf] (0,0.1]    (0,0.1]    (0.1,0.2] 
# [36] (0.1,0.2]  (0.2,0.3]  (0.2,0.3]  (0.2,0.3]  (0.2,0.3]  (0.5, Inf] (0.5, Inf]
# [43] (0.2,0.3]  (0.2,0.3]  (0,0.1]    (0,0.1]    (0,0.1]    (0,0.1]    (0.3,0.4] 
# [50] (0.3,0.4]  (0.3,0.4]  (0.3,0.4]  (0.3,0.4]  (0.3,0.4]  (0.3,0.4]  (0.3,0.4] 
# [57] (0.2,0.3]  (0.2,0.3]  (-Inf,0]   (-Inf,0]   (0.3,0.4]  (0.3,0.4]  (0.1,0.2] 
# [64] (0.1,0.2]  (0.3,0.4]  (0.3,0.4]  (0.3,0.4]  (0.3,0.4]  (0,0.1]    (0,0.1]   
# [71] (0.3,0.4]  (0.3,0.4] 
# 7 Levels: (-Inf,0] (0,0.1] (0.1,0.2] (0.2,0.3] (0.3,0.4] ... (0.5, Inf]

You may want to customize the second argument ("breaks") to represent the breaks you are actually looking for as well as look into some of the other arguments that can be passed to the cut function.