Group value in range r

Question

I have my table(input)

name   value
Rob    35
Helen  20
Sergey 16
Linn   40
Elena  23
Mary   40

And I want to count how many of my users is

Answer 1

Using dplyr, you can create (mutate) a new column indicating in which interval the value belongs (using cut) and then use this column to group your values and count (n()) how many of them you have:

library(dplyr)
df %>% mutate(cuts = cut(value, c(0, 20, 30, Inf))) %>% 
  group_by(cuts) %>% 
  summarize(n=n())

#     cuts     n
#     (fctr) (int)
# 1   (0,20]     2
# 2  (20,30]     1
# 3 (30,Inf]     3