![]() ![]() I don't know, it's been a while since I've done this, but thought I should point this out. HOWEVER, I've never liked doing this because not only is it slow, but if you vectorise it and apply a vector of URLs, if internet explorer crashes on a bad page, then R might hang or crash itself (I don't think ?try helps that much in this case). I have data in text format that is the patients complaints in an emergency department. Ie <- COMCreate("InternetExplorer.Application") So I have been searching for a long time on methods to correct typos in text in R, without manually adding/replacing words. Another way, which works almost perfectly I think at web scraping all text from html is the following (basically getting Internet Explorer to do the conversion for you): library(RDCOMClient) There may be some problems with this approach, but I can't remember what they are off the top of my head (I don't think my xpath expression works with all web pages, sometimes it might not filter out script code or it may plain just not work with some other pages at all, best to experiment!) Txt <- xpathApply(html, "//body//text()", xmlValue) Html <- htmlTreeParse(doc, useInternal = TRUE) It is an R-interface to the libxml2 library.Īnyways, here's what you do (minimal code, but options are available, see help pages of corresponding functions): u <- "" We use XML to parse the HTML code with our XPath expressions. It is an R-interface to the libtidy library. We use RTidyHTML to clean up malformed HTML web pages so that they are easier to parse. It is an R-interface to the libcurl library. It has lots of options which allow you to access websites that the default functions in base R would have difficulty with I think it's fair to say. ![]() We use RCurl to connect to the website of interest. ![]() You will need these packages installed from the repository at library(RCurl) (Note the lowercase spelling of these terms.) a To learn how to see this hypertext markup, and to save an edit, see Help:Editing. One way of doing it is to make use of XPath expressions. The markup language called wikitext, also known as wiki markup or wikicode, consists of the syntax and keywords used by the MediaWiki software to format a page. ![]()
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