![]() ![]() Plain.text <- xpathSApply(doc, "//text()", xmlValue) However, we also need to account for text we don’t want such as style and script codes, which we can do as follows: # load packages So we need to be more liberal by using “//text()” which will return all text outside of HTML tags which is what the regex approach above might give. However, there are cases where it would not work so well, such as if you wanted all the text off of a google search page (though it applies to other pages too of course): # load packages That’s a great approach for most webpages such as blogs because of the way they are designed. # I just got back from watching a production of Cool Hand Luke at the Aldwych Theatre in Central London. Plain.text <- xpathSApply(doc, "//p", xmlValue) Html <- getURL("", followlocation = TRUE) The typical technique used it seems to me is to only extract the text between paragraph tags “ The code above would not give the desired result on the real world example I give below.Īnother approach is to use XPath. This approach would require building more and more sophsiticated regular expressions, or filtering through a series of different regular expressions, to get the desired result when taking into account these diversions. However, it is meant for the browser to tell it how to do something – it’s not meant to be displayed in the web browser for the end user to see and thus is not something we want to include in our html-to-text conversion. There seems like there could be a lot of pitfalls with this approach such as what to do about tags which hold programming code for the browser between them? The code is plain text because it’s outside of the pointed brackets and would thus be extracted by the regex. I’m still learning regex and I must confess to finding this one slightly intimidating. It’s a pretty smart regex because it recognises the difference between “ which are used for a HTML tag and “” which are used as a natural part of the plain text we want. I got the regular expression in “pattern” in the code above from a quick google search which gave this webpage from 2004. This is a statement which says that 2 9 = TRUE. Input ” if it looks like a tag and rips it out e.g., # html code # assign input (could be a html file, a URL, html text, or some combination of all three is the form of a vector) I wrote a function to do this which works as follows (code can be found on github): # load packages Converting HTML to plain text usually involves stripping out the HTML tags whilst preserving the most basic of formatting.
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