我对 rvest package 有什么误解？

Question

I have trouble with scraping using rvest package in r. What I attempted was to collect information from the website and create a data frame which contains vectors specified inside the loop.

Unless I use for loop function, I get correct data. Can anybody kindly tell me what's wrong with the following code?

My hunch is that I failed in combining vectors...

library(rvest)
library(dplyr)
library(tidyr)
library(stringr)
library(stringi)


#This is the URL from which I would like to get information.
source_url <- "https://go2senkyo.com/local/senkyo/"
senkyo <- data.frame() 

*start for loop
for (i in 50:60) { 

target_page <- paste0(source_url, i)
recall_html <- read_html(source_url, encoding = "UTF-8")


prefecture <- recall_html %>%
        html_nodes(xpath='//*[contains(concat( " ", @class, " " ), concat( " ", "column_ttl_small", " " ))]') %>%
        html_text()

city <- recall_html %>%
    html_nodes(xpath='//*[contains(concat( " ", @class, " " ), concat( " ", "column_ttl", " " ))]') %>%
    html_text()
city <- trimws(gsub("[\r\n]", "", city )) %>% unlist() %>% str


candidate <- recall_html %>%
    html_nodes(xpath='//*[contains(concat( " ", @class, " " ), concat( " ", "m_senkyo_result_table", " " ))]') %>%
    html_text()
candidate  <- trimws(gsub("[\r\n\t]", "", candidate ))

all <- recall_html %>%
    html_nodes(xpath='//td') %>%
    html_text() 
all <- trimws(gsub("[\r\n\t]", "", all))

election_day <- all[1]
turnout  <- all[2]
magnitude_candidates <- all[3] 
notificationday <- all[4]
turnout_lasttime <- all[5]
others <- all[6]



senkyo2 <- cbind(prefecture, city, candidate, election_day, turnout, magnitude_candidates, notificationday,
        turnout_lasttime, others) 
senkyo  <- rbind(senkyo , senkyo2) 

}

Answer 1

Here seems to be your error:

recall_html <- read_html(source_url, encoding = "UTF-8")

It should use target_page instead of source_url

recall_html <- read_html(target_page, encoding = "UTF-8")