Question

I have a parse a web and now I want to navigate through the tags, or show a graph.
How can I get a graph? Or navigate through the tree. Showing the first step then other,etc. And understant how the tree was built.

import urllib
from lxml import etree
import StringIO
resultado=urllib.urlopen('trozo.html')
html = resultado.read()
parser= etree.HTMLParser()
tree=etree.parse(StringIO.StringIO(html),parser)

I only want to examine the nodes! A graph will be cool but I only want to examine it!

Answer 1

You achieved the parsing, which you can see if you do the following:

>>> tree
<lxml.etree._ElementTree object at 0x0148AF08>

Now you can go through this element using lxml._ElementTree functions, documented here: http://lxml.de/tutorial.html

Here are some basics, with a simple file I got from my local network:

>>> tree.getroot()
<Element html at 147aae0>
>>> tree.getroot().tag
'html'
>>> tree.getroot().text
>>> for child in tree.getroot().getchildren():
        print child.tag, child.getchildren()
head
body
>>> for child in tree.getroot().getchildren():
        print child.tag, [sub_child.tag for sub_child in child.getchildren()]
head ['title']
body ['h1', 'p', 'hr', 'address']