Question

我正在尝试将RSentiment :: calculate_score（）应用于存储在data.frame中的一组句子。以下是我获取数据的方式：

install.packages("pacman")
pacman::p_load(XML, dplyr, tidyr, stringr, rvest, audio, xml2, purrr, tidytext, ggplot2)

sapiens_code = "1846558239"
deus_ex_code = "1910701874"

function_product <- function(prod_code){
  url <- paste0("https://www.amazon.co.uk/dp/",prod_code)
  doc <- xml2::read_html(url)
  prod <- html_nodes(doc,"#productTitle") %>% html_text() %>%
    gsub("\n","",.) %>%
    gsub("^\\s+|\\s+$", "", .) #Remove all white space
  prod
}

sapiens <- function_product(sapiens_code)
deus_ex <- function_product(deus_ex_code)

#Source function to Parse Amazon html pages for data 
source("https://raw.githubusercontent.com/rjsaito/Just-R-Things/master/Text%20Mining/amazonscraper.R")

# extracting reviews 
pages <- 13

function_page <- function(page_num, prod_code){
  url2 <- paste0("http://www.amazon.co.uk/product-reviews/",prod_code,"/?pageNumber=", page_num)
  doc2 <- read_html(url2)

  reviews <- amazon_scraper(doc2, reviewer = F, delay = 2)
  reviews
}

sapiens_reviews <- map2(1:pages, sapiens_code, function_page) %>%   bind_rows()

deusex_reviews <- map2(1:pages, deus_ex_code, function_page) %>% bind_rows()

sapiens_reviews$comments <- gsub("\\.", "\\. ",   sapiens_reviews$comments)
deusex_reviews$comments <- gsub("\\.", "\\. ", deusex_reviews$comments)

sentence_function <- function(df){
  df_sentence <- df %>% 
    select(comments, format, stars, helpful) %>% 
    unnest_tokens(sentence, comments, token = "sentences")
  df_sentence
}

sapiens_sentence <- sentence_function(sapiens_reviews)
deusex_sentence <- sentence_function(deusex_reviews)

但是当我尝试为他们分配分数时，我收到一个错误：

 deusex_sentence <- deusex_sentence %>% 
   mutate(sentence_score <- unname(calculate_score(sentence)))

错误：参数意味着行数不同：34,33

我看不到输入格式的任何根本错误，随机选择的句子的输出似乎很好，例如。

unname(calculate_score(sapiens_sentence[1, 4]))
[1] -1

任何想法如何解决这个问题？非常感谢你的帮助！

Answer 1

事实证明，问题是由句子中的特殊字符引起的。删除后，我可以成功运行情绪分析（我在函数中包含了数据清理步骤）：

sentence_function <- function(df){
  df_sentence <- df %>% 
    select(comments, format, stars, helpful) %>% 
    unnest_tokens(sentence, comments, token = "sentences") %>%
    mutate(sentence2 = str_replace_all(sentence, "[^[:alnum:]]", " ")) #removing all special characters

  df_sentence <- df_sentence  %>%
    mutate(sentence_score = unname(calculate_score(sentence2))) 

  df_sentence
}

# go and get a hot drink while this is running 
sapiens_sentence <- sentence_function(sapiens_reviews)
deusex_sentence <- sentence_function(deusex_reviews)

R：RSentiment :: calculate_score（）返回“错误：参数意味着不同的行数”

1 个答案: