CODEWITHSUNDEEP
rdplyrmaxsummarize
Bear
Bear

Reputation: 690

Pass a vector of column names into dplyr::summarize to get max/min

I would like to do this:

data %>%
    group_by(ID) %>%
    summarize(maxVal = max(Val),
              maxVal2 = max(Val2))

However, I have a lot of columns I would like to get the Max of. I would like to pass in a vector of columns like this:

cols <- c("Val", "Val2")
data %>%
    group_by(ID) %>%
    summarize(max(cols))

However, this does not work. How do I fix the syntax to do this easily?

Upvotes: 1

Views: 574

Answers (1)

akrun
akrun

Reputation: 887991

If we wanted to have a prefix name after summarizeing the multiple columns, then use rename_at

library(tidyverse)
data %>%
   group_by(ID) %>%
   summarise_at(vars(cols), max) %>%
   rename_at(-1, ~ paste0('max', .))

As a reproducible example, used the data(mtcars)

mtcars %>% 
  group_by(gear) %>% 
  summarise_at(vars(mpg, disp), max) %>% 
  rename_at(-1, ~ paste0('max', .))
# A tibble: 3 x 3
#   gear maxmpg maxdisp
#  <dbl>  <dbl>   <dbl>
#1     3   21.5    472 
#2     4   33.9    168.
#3     5   30.4    351

Upvotes: 1

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