convert email to lower to get count

[shoaibali]

I have a very big data of email id like below

Email
abc@LIVE.com
dfg@live.com
bhjus@Hotmail.com
bhuio@hotmail.com

now i am trying to create a summary of domain counts, i am trying like below but its very time taking , i am getting count of two domain count for lower case and upper case
domain count
HOTMAIL 1
hotmail 1

domain_ct <- df %>% select(Email) %>% filter(!is.na(Email)) %>% tolower(Email)
domain_ct <- as.data.frame(table(sub(".*@", "",domain_ct$Email )))

getting error
Error in tolower(., Email) : unused argument (Email)

do we have any other solution for this.....

[FJCC]

The problem is that tolower takes as its first argument the vector to be changed and when you put it in a chain with %>% you are passing it the data frame produced by filter() and then Email. Try this as your first step.

domain_ct <- df %>% select(Email) %>% filter(!is.na(Email)) %>%
  mutate(Email = tolower(Email))

[elmstedt]

Alternately, here is a {base} R solution,

email <- c("abc@LIVE.com",
           "dfg@live.com",
           "bhjus@Hotmail.com",
           "bhuio@hotmail.com")
table(tolower(vapply(strsplit(email, "@"), `[[`, character(1), 2)))
#> 
#> hotmail.com    live.com 
#>           2           2

^{Created on 2020-09-14 by the reprex package (v0.3.0)}