Group by multiple columns and sum other multiple columns

Question

I have a data frame with about 200 columns, out of them I want to group the table by first 10 or so which are factors and sum the rest of the columns.

I have list of

Answer 1

Let's consider this example :

df <- data.frame(a = 'a', b = c('a', 'a', 'b', 'b', 'b'), c = 1:5, d = 11:15,
                 stringsAsFactors = TRUE)

_all, _at and _if verbs are now superseded and we use across now to group all the factor columns and sum all the other columns, we can do :

library(dplyr)

df %>% 
   group_by(across(where(is.factor))) %>% 
   summarise(across(everything(), sum))

#  a     b         c     d
#     
#1 a     a         3    23
#2 a     b        12    42

To group all factor columns and sum numeric columns :

df %>% 
  group_by(across(where(is.factor))) %>% 
  summarise(across(where(is.numeric), sum))

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We can also do this by position but have to be careful of the number since it doesn't count the grouping columns.

df %>% group_by(across(1:2)) %>% summarise(across(1:2, sum))