r-如何使用自定义分隔符将语料库分解为段落

Question

我正在抓取《纽约时报》的网页，对其进行一些自然语言处理，我想在使用语料库时将网页拆分为段落，以便对出现在段落中的单词进行频率计数，这些段落也包含关键字或短语。

以下内容适用于句子，但段落是由《纽约时报》的一位•捐赠的，所以我需要将其替换为语料库如何阅读段落——有人知道吗？我试过gsub("•"，"/n"，…(和gsub("•"，"/r/n"(，但都没用。

如果有人知道如何在tm语料库中完成这一切，而不必在quanteda和tm之间切换，这将节省一些代码。

website<-read_html("https://www.nytimes.com/2017/01/03/briefing/asia-australia-briefing.html") #Read URL


#Obtain any text with the paragraph Html deliminator 
text<-website%>%
html_nodes("p") %>%
html_text() %>% as.character()

#Collapse the string as it is currently text[1]=para1 and text[2]= para 2
text<- str_c(text,collapse=" ")

data_corpus_para <- 
corpus_reshape(corpus((text),to="paragraphs"))

data_corpus_para <-tolower(data_corpus_para )

containstarget <- 
stringr::str_detect(texts(data_corpus_para ), "pull out of peace talks") #Random string in only one of the paragraphs to proof concept
#Filter for the para's that only contain the sentence above
data_corpus_para <- 
corpus_subset(data_corpus_para , containstarget)                 
data_corpus_para <-corpus_reshape(data_corpus_para , to = "documents")

#There are quanteda corpus and TM Corpuses. And so I have to convert to a dataframe and then make back into a vcorupus.. this is very messy
data_corpus_para <-quanteda::convert(data_corpus_para )
data_corpus_para_VCorpus<-tm::VCorpus(tm::VectorSource(data_corpus_para$text))
dt.dtm = tm::DocumentTermMatrix(data_corpus_para_VCorpus)
tm::findFreqTerms(dt.dtm, 1)

Answer 1

如果段落分隔符为"•&"；，则可以使用corpus_segment():

library("quanteda")
## Package version: 3.0.0
## Unicode version: 10.0
## ICU version: 61.1
## Parallel computing: 12 of 12 threads used.
## See https://quanteda.io for tutorials and examples.
txt <- "
• This is the first paragraph.
This is still the first paragraph.
• Here is the third paragraph.  Last sentence"
corpus(txt) %>%
corpus_segment(pattern = "•")
## Corpus consisting of 2 documents and 1 docvar.
## text1.1 :
## "This is the first paragraph. This is still the first paragra..."
## 
## text1.2 :
## "Here is the third paragraph.  Last sentence"

^{创建于2021-04-10由reprex包(v1.0.0(}