Swish Project Something I Prepared Earlier

1
Swish ProjectSomething I Prepared Earlier

• Graham Klyne
• http//www.ninebynine.org/
• 5 November 2004
• http//www.ninebynine.org/Presentations/20041105-S
  wish-Project.ppt
• http//www.ninebynine.org/Presentations/20041105-S
  wish-Project.pdf

2
About Swish

• My Swish project
• experimental Semantic Web data processing
• inspired by CWM (its strengths and and its
  shortcomings)
• developed in Haskell
• some features
• parsers Notation 3, RDF/XML, CSV
• output writer Notation 3
• multiple inference rule styles Horn rule,
  class-based
• scriptable
• exploration of datatype inference
• graph comparison and differencing
• Description Logic inference (work in progress)

3
A closer look at two features

• Graph differencing
• possible use for evaluating or isolating changes
  in ontology definitions
• Importing RDF data from spreadsheets
• possible relevance to integration of existing
  data sources into Semantic Web applications

4
Graph differencing (1)

• Related to graph isomorphism testing
• roughly structural equivalence testing
• cf. paper by Jeremy Carroll
• The difficulty bnodes
• correspondence between URI-labelled nodes or
  literal nodes is easily determined
• determining a correspondence between bnodes
  requires an analysis of the graph structure
• there may be more than one satisfying
  correspondence between bnodes

5
Graph differencing (2)

• My approach
• Partition graphs into subtrees
• Each subtree root is a statement subject that is
  a URI node or a blank node that is not the object
  of exactly one statement
• Compare URI-rooted subtrees
• Compare all pairs of bnode-rooted subtrees
• Although my approach would perform poorly in
  awkward cases, I claim it effectively exploits
  patterns commonly found in RDF data

6
Graph difference example

• hdrRFC1766 a hdrSpecification_doc
• hdrdocument rfcedrfc1766.txt
• hdrauthor
• foafname "H. Alvestrand"
• hdrtitle "Tags for the Identification of
  Languages"
• hdrstatus "standards-track"
• hdrdate "March 1995" .
• hdrRFC1864 a hdrSpecification_doc
• hdrdocument rfcedrfc1864.txt
• hdrauthor
• foafname "J. Myers"
• hdrauthor
• foafname "M. Rose"
• hdrtitle "The Content-MD5 Header Field"
• hdrstatus "standards-track"
• hdrdate "October 1995" .

• hdrRFC1864 a hdrSpecification_doc
• hdrauthor
• foafname "M.T. Rose"
• hdrauthor
• foafname "J. Myers"
• hdrtitle "The Content-MD5 Header Field"
• hdrdocument rfcedrfc1864.txt
• hdrstatus "standards-track"
• hdrlabel "RFC 1864"
• hdrdate "October 1995" .
• hdrRFC1766 a hdrSpecification_doc
• hdrdocument rfcedrfc1766.txt
• hdrtitle "Tags for the Identification of
  Languages"
• hdrstatus "standards-track"
• hdrdate "March 1995"
• hdrauthor
• foafname "H. Alvestrand" .

7
Importing spreadsheet data

• Not all interesting data is RDF ...
• but may be presented as RDF
• Example URI test data from spreadsheet

8
Data exported as CSV

• ,Test data for URI parsing,,,,,,,,,,,,
• _at_prefix,uri,lthttp//id.ninebynine.org/wip/2004/ur
  itest/gt,,,,,,,,,,,
• _at_rowtype,uriUriTest,,,,,,,,,,,,
• _at_columns,,,,,,,,,,,,,
• rdfslabel,uritest,uribase,uriabs,urirel,rdfs
  comment,urischeme,uriauth,uriuser,urireg,urip
  ort,uripath,uriquery,urifrag
• _at_coltypes,,,,,,,,,,,,,
• _at_string,_at_resource,_at_string,_at_string,_at_string,_at_string,
  _at_string,xsdboolean,_at_string,_at_string,_at_string,_at_strin
  g,_at_string,_at_string
• _at_data,,
• Syntax001,uriAbsRf,http//example.org/aaa/bbbccc
  
• Syntax002,uriAbsId,mailtolocal_at_domain.org
• Syntax014,uriRelRf,aaa2Fbbb,,,
• Decomp01,uriDecomp,http//userpass_at_example.org9
  9/aaa/bbb?qqqfff,,,,http,True,userpass_at_,example
  .org,99,/aaa/bbb,?qqq,fff,
• Decomp02,uriDecomp,http//userpass_at_example.org9
  9aaa/bbb,,,Invalid,,False,,,,,,,
• Relative01,uriRelative,fooxyz,barabc,barabc,,,
  ,,,,,,,
• Relative02,uriRelative,http//example/x/y/z,http
  //example/x/abc,../abc,,,,,,,,,,
• _at_end,,,

9
Reinterpretation as RDF/N3

• _at_prefix rdf lthttp//www.w3.org/1999/02/22-rdf-syn
  tax-nsgt .
• _at_prefix rdfs lthttp//www.w3.org/2000/01/rdf-schem
  agt .
• _at_prefix xsd lthttp//www.w3.org/2001/XMLSchemagt
  .
• _at_prefix uri lthttp//id.ninebynine.org/wip/2004/ur
  itest/gt .
• __1 uribase "http//example.org/aaa/bbbccc"
• uritest uriAbsRf
• rdftype uriUriTest
• rdfslabel "Syntax001" .
• __2 uribase "mailtolocal_at_domain.org"
• uritest uriAbsId
• rdftype uriUriTest
• rdfslabel "Syntax002" .
• __3 uribase "aaa2Fbbb"
• uritest uriRelRf
• rdftype uriUriTest
• rdfslabel "Syntax014" .
• __4 uriauth "True"xsdboolean
• uribase "http//userpass_at_example.org99/aaa
  /bbb?qqqfff"
• urifrag "fff"

• __5 uriauth "False"xsdboolean
• uribase "http//userpass_at_example.org99aaa/
  bbb"
• uritest uriDecomp
• rdftype uriUriTest
• rdfscomment "Invalid"
• rdfslabel "Decomp02" .
• __6 uriabs "barabc"
• uribase "fooxyz"
• urirel "barabc"
• uritest uriRelative
• rdftype uriUriTest
• rdfslabel "Relative01" .
• __7 uriabs "http//example/x/abc"
• uribase "http//example/x/y/z"
• urirel "../abc"
• uritest uriRelative
• rdftype uriUriTest
• rdfslabel "Relative02" .

10
End

• Contact information
• gk_at_ninebynine.org
• http//www.ninebynine.org/
• References
• http//www.ninebynine.org/RDFNotes/Swish/Intro.htm
  l
• http//www.ninebynine.org/RDFNotes/Intro.html
• http//www.ninebynine.org/Software/Intro.html
• http//www.ninebynine.org/SWAD-E/Intro.html
• http//www.ninebynine.org/Software/HaskellDL/DLExp
  loration.lhs