R - web scraping through multiple URLs? with rvest and purrr

问题

I am trying to scrape football(soccer) statistics for a project i'm working on and i'm trying to utilise rvest and purrr to loop through the numeric values at the end of the url. I'm not sure what i'm missing but i have a snippet of the code as well as the error message that keeps coming up.

library(xml2)

library(rvest)

library(purrr) 

wins_URL <- "https://www.premierleague.com/stats/top/clubs/wins?se=%d"

map_df(1:15, function(i){

  cat(".")
  page <- read_html(sprintf(wins_URL, i))

  data.frame(statTable = html_table(html_nodes(page,"td , th")))

}) -> WinsTable

Error in doc_namespaces(doc) : external pointer is not valid

I've only recently started using R so I'm no expert and would just like to know what mistakes I'm making

来源：https://stackoverflow.com/questions/51159150/r-web-scraping-through-multiple-urls-with-rvest-and-purrr