I have the following dataframe:
df<-data.frame(city=c("Berlin","Berlin","Frankfurt","Frankfurt","Frankfurt"),
item=c("A","B","A","D","E"))
df
#> city item
#> 1 Berlin A
#> 2 Berlin B
#> 3 Frankfurt A
#> 4 Frankfurt D
#> 5 Frankfurt E
I would like to achieve the following:
#> city items
#> 1 Berlin A,B
#> 2 Frankfurt A,D,E
How do I do that preferably with dplyr?