For example, the data is:
a <- tibble(id=1:2,
text=c('aaa. bb cc. d','a b c. sdf afd. fer fer fe fe. def'))
I want for the column text, I use '.' to split each string into multiple strings. Then put the new strings into a new data frame, like:
id text
1 aaa
1 bb cc
1 d
2 a b c
2 sdf afd
2 fer fer fe fe
2 def
I guess apply family can do this, But I just do not know how.