In R: get multiple rows by splitting a column using tidyr and reshape2 [duplicate]

Answer 1

Try

library(splitstackshape)
 cSplit(data, 'B', ',', 'long')

Or using base R

lst <- setNames(strsplit(as.character(data$B), ','), data$A)
stack(lst)

Or

library(tidyr)
 unnest(lst,A)