Re: [R] XML package example code?

2009-11-25 Thread Tony B
It's been a long time since i read the tutorials, but 'I think', the
reason you get those notifications is because the html code is
malformed, meaning that some of the opening tags '' don't have
corresponding end tags  etc.

The XML package seems rather good at working with malformed code, and
therefore I usually just force those notifications into an empty
function.


library(RCurl)
library(XML)
html <- getURL("http://www.omegahat.org/RSXML/index.html";)
html.tree <- htmlTreeParse(html, useInternalNodes = TRUE, error =
function(...){})

HTH,
Tony Breyal


On 25 Nov, 16:21, Peng Yu  wrote:
> On Wed, Nov 25, 2009 at 12:19 AM, cls59  wrote:
>
> > 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/
>
> http://www.omegahat.org/RSXML/shortIntro.html
>
> I'm trying the example on the above webpage. But I'm not sure why I
> got the following error. Would you help to take a look?
>
> $ Rscript main.R> library(XML)
>
> > download.file('http://www.omegahat.org/RSXML/index.html','index.html')
>
> trying URL 'http://www.omegahat.org/RSXML/index.html'
> Content type 'text/html; charset=ISO-8859-1' length 3021 bytes
> opened URL
> ==
> downloaded 3021 bytes
>
>
>
> > doc = xmlInternalTreeParse("index.html")
>
> Opening and ending tag mismatch: dd line 68 and dl
> Opening and ending tag mismatch: li line 67 and body
> Opening and ending tag mismatch: dt line 66 and html
> Premature end of data in tag dd line 64
> Premature end of data in tag li line 63
> Premature end of data in tag dt line 62
> Premature end of data in tag dl line 61
> Premature end of data in tag body line 5
> Premature end of data in tag html line 1
> Error: 1: Opening and ending tag mismatch: dd line 68 and dl
> 2: Opening and ending tag mismatch: li line 67 and body
> 3: Opening and ending tag mismatch: dt line 66 and html
> 4: Premature end of data in tag dd line 64
> 5: Premature end of data in tag li line 63
> 6: Premature end of data in tag dt line 62
> 7: Premature end of data in tag dl line 61
> 8: Premature end of data in tag body line 5
> 9: Premature end of data in tag html line 1
> Execution halted
>
> __
> r-h...@r-project.org mailing listhttps://stat.ethz.ch/mailman/listinfo/r-help
> PLEASE do read the posting guidehttp://www.R-project.org/posting-guide.html
> and provide commented, minimal, self-contained, reproducible code.

__
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and provide commented, minimal, self-contained, reproducible code.


Re: [R] XML package example code?

2009-11-25 Thread Tony B
Not sure if my code was attached in that last post:

library(RCurl)
library(XML)
html <- getURL("http://www.omegahat.org/RSXML/index.html";)
html.tree <- htmlTreeParse(html, useInternalNodes = TRUE, error =
function(...){})


On 25 Nov, 16:21, Peng Yu  wrote:
> On Wed, Nov 25, 2009 at 12:19 AM, cls59  wrote:
>
> > 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/
>
> http://www.omegahat.org/RSXML/shortIntro.html
>
> I'm trying the example on the above webpage. But I'm not sure why I
> got the following error. Would you help to take a look?
>
> $ Rscript main.R> library(XML)
>
> > download.file('http://www.omegahat.org/RSXML/index.html','index.html')
>
> trying URL 'http://www.omegahat.org/RSXML/index.html'
> Content type 'text/html; charset=ISO-8859-1' length 3021 bytes
> opened URL
> ==
> downloaded 3021 bytes
>
>
>
> > doc = xmlInternalTreeParse("index.html")
>
> Opening and ending tag mismatch: dd line 68 and dl
> Opening and ending tag mismatch: li line 67 and body
> Opening and ending tag mismatch: dt line 66 and html
> Premature end of data in tag dd line 64
> Premature end of data in tag li line 63
> Premature end of data in tag dt line 62
> Premature end of data in tag dl line 61
> Premature end of data in tag body line 5
> Premature end of data in tag html line 1
> Error: 1: Opening and ending tag mismatch: dd line 68 and dl
> 2: Opening and ending tag mismatch: li line 67 and body
> 3: Opening and ending tag mismatch: dt line 66 and html
> 4: Premature end of data in tag dd line 64
> 5: Premature end of data in tag li line 63
> 6: Premature end of data in tag dt line 62
> 7: Premature end of data in tag dl line 61
> 8: Premature end of data in tag body line 5
> 9: Premature end of data in tag html line 1
> Execution halted
>
> __
> r-h...@r-project.org mailing listhttps://stat.ethz.ch/mailman/listinfo/r-help
> PLEASE do read the posting guidehttp://www.R-project.org/posting-guide.html
> and provide commented, minimal, self-contained, reproducible code.

__
R-help@r-project.org mailing list
https://stat.ethz.ch/mailman/listinfo/r-help
PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
and provide commented, minimal, self-contained, reproducible code.


Re: [R] XML package example code?

2009-11-25 Thread Duncan Temple Lang


Peng Yu wrote:
> On Wed, Nov 25, 2009 at 12:19 AM, cls59  wrote:
>>
>> 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/
> 
> 
> http://www.omegahat.org/RSXML/shortIntro.html
> 
> I'm trying the example on the above webpage. But I'm not sure why I
> got the following error. Would you help to take a look?
> 
> 
> $ Rscript main.R
>> library(XML)
>>
>> download.file('http://www.omegahat.org/RSXML/index.html','index.html')
> trying URL 'http://www.omegahat.org/RSXML/index.html'
> Content type 'text/html; charset=ISO-8859-1' length 3021 bytes
> opened URL
> ==
> downloaded 3021 bytes
> 
>> doc = xmlInternalTreeParse("index.html")


You are trying to parse an HTML document as if it were XML.
But HTML is often not well-formed.  So use htmlParse()
for a more forgiving parser.

Or use the RTidyHTML package (www.omegahat.org/RTidyHTML)
to make the HTML well-formed before passing it to xmlTreeParse()
(aka xmlInternalTreeParse()). That package is an interface to
libtidy.

 D.


> Opening and ending tag mismatch: dd line 68 and dl
> Opening and ending tag mismatch: li line 67 and body
> Opening and ending tag mismatch: dt line 66 and html
> Premature end of data in tag dd line 64
> Premature end of data in tag li line 63
> Premature end of data in tag dt line 62
> Premature end of data in tag dl line 61
> Premature end of data in tag body line 5
> Premature end of data in tag html line 1
> Error: 1: Opening and ending tag mismatch: dd line 68 and dl
> 2: Opening and ending tag mismatch: li line 67 and body
> 3: Opening and ending tag mismatch: dt line 66 and html
> 4: Premature end of data in tag dd line 64
> 5: Premature end of data in tag li line 63
> 6: Premature end of data in tag dt line 62
> 7: Premature end of data in tag dl line 61
> 8: Premature end of data in tag body line 5
> 9: Premature end of data in tag html line 1
> Execution halted
> 
> __
> R-help@r-project.org mailing list
> https://stat.ethz.ch/mailman/listinfo/r-help
> PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
> and provide commented, minimal, self-contained, reproducible code.

__
R-help@r-project.org mailing list
https://stat.ethz.ch/mailman/listinfo/r-help
PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
and provide commented, minimal, self-contained, reproducible code.


Re: [R] XML package example code?

2009-11-25 Thread Peng Yu
On Wed, Nov 25, 2009 at 12:19 AM, cls59  wrote:
>
>
> 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/


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

I'm trying the example on the above webpage. But I'm not sure why I
got the following error. Would you help to take a look?


$ Rscript main.R
> library(XML)
>
> download.file('http://www.omegahat.org/RSXML/index.html','index.html')
trying URL 'http://www.omegahat.org/RSXML/index.html'
Content type 'text/html; charset=ISO-8859-1' length 3021 bytes
opened URL
==
downloaded 3021 bytes

>
> doc = xmlInternalTreeParse("index.html")
Opening and ending tag mismatch: dd line 68 and dl
Opening and ending tag mismatch: li line 67 and body
Opening and ending tag mismatch: dt line 66 and html
Premature end of data in tag dd line 64
Premature end of data in tag li line 63
Premature end of data in tag dt line 62
Premature end of data in tag dl line 61
Premature end of data in tag body line 5
Premature end of data in tag html line 1
Error: 1: Opening and ending tag mismatch: dd line 68 and dl
2: Opening and ending tag mismatch: li line 67 and body
3: Opening and ending tag mismatch: dt line 66 and html
4: Premature end of data in tag dd line 64
5: Premature end of data in tag li line 63
6: Premature end of data in tag dt line 62
7: Premature end of data in tag dl line 61
8: Premature end of data in tag body line 5
9: Premature end of data in tag html line 1
Execution halted

__
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Re: [R] XML package example code?

2009-11-25 Thread Tony B
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  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?
>
> __
> r-h...@r-project.org mailing listhttps://stat.ethz.ch/mailman/listinfo/r-help
> PLEASE do read the posting guidehttp://www.R-project.org/posting-guide.html
> and provide commented, minimal, self-contained, reproducible code.

__
R-help@r-project.org mailing list
https://stat.ethz.ch/mailman/listinfo/r-help
PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
and provide commented, minimal, self-contained, reproducible code.


Re: [R] XML package example code?

2009-11-24 Thread cls59


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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[R] XML package example code?

2009-11-24 Thread Peng Yu
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?

__
R-help@r-project.org mailing list
https://stat.ethz.ch/mailman/listinfo/r-help
PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
and provide commented, minimal, self-contained, reproducible code.