How to aggregate data in data.frame in R

Question

I have a large data.frame. The data.frame include a lot of values.

For example:

df <- data.frame(Company = c(\'A\', \'A\', \'B\', \'C\', \'A\', \'         


        

Answer 1

One option is using data.table

library(data.table)
setDT(df)[, c(lapply(.SD[, c(2:3, 5), with = FALSE], mean), 
    .(Education.University = sum(Education.University))), by = Company]
#   Company      Age    Wages Productivity Education.University
#1:       A 27.00000 56666.67     102.6667                    2
#2:       B 28.66667 68333.33     111.6667                    3
#3:       C 29.00000 53333.33     101.6667                    1

---

Or with dplyr

library(dplyr)
df %>%
   group_by(Company) %>% 
   mutate(Education.University = sum(Education.University)) %>%
   summarise_if(is.numeric, mean)
# A tibble: 3 x 5
#  Company      Age    Wages Education.University Productivity
#                                   
#1       A 27.00000 56666.67                    2     102.6667
#2       B 28.66667 68333.33                    3     111.6667
#3       C 29.00000 53333.33                    1     101.6667