Cumulative total by group

Question

For the following dataset:

d = data.frame(date = as.Date(as.Date(\'2015-01-01\'):as.Date(\'2015-04-10\'), origin = \"1970-01-01\"),
               group = re         


        

Answer 1

This should work

library(dplyr)
d %>% 
  group_by(group) %>% 
  arrange(date) %>% 
  mutate(Total = cumsum(value))