R help - Nov 2009 - XML package example code?

I'm interested in parsing an html page. I should use XML, right? Could
you somebody show me some example code? Is there a tutorial for this
package?

Peng Yu wrote:
> 
> I'm interested in parsing an html page. I should use XML, right? Could
> you somebody show me some example code? Is there a tutorial for this
> package?
> 
Did you try looking through the help pages for the XML package or browsing
the Omegahat website?

Look at:

  library(XML)
  ?htmlTreeParse

And the relevant web page for documentation and examples is:

  http://www.omegahat.org/RSXML/


-Charlie

-----
Charlie Sharpsteen
Undergraduate
Environmental Resources Engineering
Humboldt State University
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Cls59 is correct that there is a lot of example code, just look in ?
htmlTreeParse and you'll get most of what you need i think.

here's some simplified code I use a lot of (XPath expressions are used
to parse the code):

# libraries
library(RCurl)
library(XML)

# google url
my.url <- "http://www.google.co.uk/search?hl=en&client=firefox-
a&rls=org.mozilla%3Aen-GB%3Aofficial&hs=6Sd&q=google
+wave&btnG=Search&meta=&aq=f&oq="

# download page
html <- getURL(my.url)
html.tree <- htmlTreeParse(html, useInternalNodes = TRUE, error
function(...){})

# the xpath expression is next
nodes <- getNodeSet(html.tree, "//a[@href][@class='l']")
links <- sapply(nodes, function(x) x <- xmlAttrs(x)[[1]])


HTH
Tony

On 25 Nov, 01:49, Peng Yu <pengyu... at gmail.com>
wrote:
> I'm interested in parsing an html page. I should use XML, right? Could
> you somebody show me some example code? Is there a tutorial for this
> package?
>
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