Hi Rob
doc = xmlParse("url for document")
dn = getNodeSet(doc, "//descriptorna...@majortopic = 'Y']")
will do what you want, I believe.
XPath - a language for expressing such queries - is quite
simple and based on a few simple primitive concepts from which
one can create complex compound queries. The //DescriptorName
is a node test. The [] is a predicate that includes/discards
some of the resulting nodes.
D.
On 9/8/10 9:09 AM, Rob James wrote:
> I am looking for the syntax to capture XML tags marked with
> /DescriptorName MajorTopicYN="Y"/ , but the combination of the internal
> space (between "Name" and "Major" and the embedded quote marks are
> defeating me. I can get all the "DescriptorName" tags, but these include
> both MajroTopicYN = "Y" and "N" variants. Any suggestions?
>
> Thanks in advance.
>
> Prototype text from PUBMED
>
> <MeshHeadingList>
> <MeshHeading>
> <DescriptorName MajorTopicYN="Y">Antibodies, Monoclonal</DescriptorName>
> </MeshHeading>
> <MeshHeading>
> <DescriptorName MajorTopicYN="N">Blood Platelets</DescriptorName>
> <QualifierName MajorTopicYN="N">immunology</QualifierName>
> <QualifierName MajorTopicYN="Y">physiology</QualifierName>
> <QualifierName MajorTopicYN="N">ultrastructure</QualifierName>
> </MeshHeading>
> </MeshHeadingList>
>
>
>
> [[alternative HTML version deleted]]
>
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