How do I solve the following error?Input must be a character vector of any length or a list of character vectors, each of which has a length of 1

Question

I am working on a R project. The data set I used is available at the following link https://www.kaggle.com/ranjitha1/hotel-reviews-city-chennai/data

The code I have used is.

df1 = read.csv("chennai.csv", header = TRUE)
library(tidytext)
tidy_books <- df1 %>% unnest_tokens(word,Review_Text)

Here Review_Text is the text column. Yet, I get the following error.

Error in check_input(x) : Input must be a character vector of any length or a list of character vectors, each of which has a length of 1.

Plural

You need stringsAsFactors=FALSE in your read.csv statement. Or use read_csv as you seem to be working in the tidyverse. – Trim

What I was about to say but in a more compact way. Consider checking out the structure of new data though before you work on it, i.e. str(df1), this would have alerted you to the problem as well – Sessions

Answer 1

stringsAsFactors strikes again!

Your Review_Text column is a factor, not a character vector as the error message says the function requires.

I would strongly recommend using readr::read_csv over the default read.csv as it's faster and its defaults don't cause this problem. Otherwise, just set stringsAsFactors to FALSE and you're good:

> tidytext::unnest_tokens(readr::read_csv("chennai_reviews.csv"), word, Review_Text)
Parsed with column specification:
cols(
  Hotel_name = col_character(),
  Review_Title = col_character(),
  Review_Text = col_character(),
  Sentiment = col_character(),
  Rating_Percentage = col_character(),
  X6 = col_integer(),
  X7 = col_integer(),
  X8 = col_character(),
  X9 = col_character()
)
Warning: 1 parsing failure.
row # A tibble: 1 x 5 col     row   col   expected                                                                                                       actual expected   <int> <chr>      <chr>                                                                                                        <chr> actual 1  2262    X7 an integer "Expedia Booking  availability was  , only  for  Non-  AC ; ON REQUEST  OVER  PHONE got  it.\n\nRecommended" file # ... with 1 more variables: file <chr>

# A tibble: 179,883 x 9
            Hotel_name                          Review_Title Sentiment Rating_Percentage    X6    X7    X8    X9       word
                 <chr>                                 <chr>     <chr>             <chr> <int> <int> <chr> <chr>      <chr>
 1 Accord Metropolitan Excellent comfortableness during stay         3               100    NA    NA  <NA>  <NA>        its
 2 Accord Metropolitan Excellent comfortableness during stay         3               100    NA    NA  <NA>  <NA>     really
 3 Accord Metropolitan Excellent comfortableness during stay         3               100    NA    NA  <NA>  <NA>       nice
 4 Accord Metropolitan Excellent comfortableness during stay         3               100    NA    NA  <NA>  <NA>      place
 5 Accord Metropolitan Excellent comfortableness during stay         3               100    NA    NA  <NA>  <NA>         to
 6 Accord Metropolitan Excellent comfortableness during stay         3               100    NA    NA  <NA>  <NA>       stay
 7 Accord Metropolitan Excellent comfortableness during stay         3               100    NA    NA  <NA>  <NA> especially
 8 Accord Metropolitan Excellent comfortableness during stay         3               100    NA    NA  <NA>  <NA>        for
 9 Accord Metropolitan Excellent comfortableness during stay         3               100    NA    NA  <NA>  <NA>   business
10 Accord Metropolitan Excellent comfortableness during stay         3               100    NA    NA  <NA>  <NA>        and
# ... with 179,873 more rows
Warning message:
Missing column names filled in: 'X6' [6], 'X7' [7], 'X8' [8], 'X9' [9] 

or

> tidytext::unnest_tokens(read.csv("chennai_reviews.csv", stringsAsFactors = FALSE), word, Review_Text)
                                                Hotel_name
1                                      Accord Metropolitan
                                                                                                                                                                                                                                                        Review_Title
...snip...

Ealasaid