The issue is because there are some list columns that are NULL
str(chat)
#tibble [2 × 6] (S3: tbl_df/tbl/data.frame)
# $ time : POSIXct[1:2], format: "2015-01-31 04:10:59" "2015-01-31 14:10:59"
# $ author : Factor w/ 2 levels "Fulanito","Menganito": 2 1
# $ text : chr [1:2] "Was it good?" "Yes, it was"
# $ source : chr [1:2] "text input" "text input"
# $ emoji :List of 2 ###
# ..$ : NULL
# ..$ : NULL
# $ emoji_name:List of 2 ###
# ..$ : NULL
# ..$ : NULL
we can remove it and it works now
library(rwhatsapp)
library(tidytext)
chat %>%
select_if(~ !is.list(.)) %>%
unnest_tokens(output = bigram, input = text, token = "ngrams", n = 2)
# A tibble: 4 x 4
# time author source bigram
# <dttm> <fct> <chr> <chr>
#1 2015-01-31 04:10:59 Menganito text input was it
#2 2015-01-31 04:10:59 Menganito text input it good
#3 2015-01-31 14:10:59 Fulanito text input yes it
#4 2015-01-31 14:10:59 Fulanito text input it was
Also, by default collapse=TRUE, and this creates an issue when there are NULL elements because the lengths gets different when it is collapsed. One option is to specify collapse = FALSE
chat %>%
unnest_tokens(output = bigram, input = text, token = "ngrams",
n = 2, collapse= FALSE)
# A tibble: 4 x 6
# time author source emoji emoji_name bigram
# <dttm> <fct> <chr> <list> <list> <chr>
#1 2015-01-31 04:10:59 Menganito text input <NULL> <NULL> was it
#2 2015-01-31 04:10:59 Menganito text input <NULL> <NULL> it good
#3 2015-01-31 14:10:59 Fulanito text input <NULL> <NULL> yes it
#4 2015-01-31 14:10:59 Fulanito text input <NULL> <NULL> it was