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</o:shapelayout></xml><![endif]--></head><body lang=EN-GB link="#0563C1" vlink="#954F72" style='word-wrap:break-word'><div class=WordSection1><p class=MsoNormal><span lang=EN-US>We discussed last week some ideas I proposed about how to create an API for RepInfo Networks.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US>Terry raised the question about algorithms to determine whether a DAG was acyclic, which is important for RINs because otherwise one could end up in an endless loop if it turned out that the RepInfo one needed for something involved itself.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US>I found <a href="http://www.dagitty.net/">http://www.dagitty.net/</a> which may have some relevant algorithms.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US>Neither I nor Steve will be on the call on Tuesday.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US>Regards<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US>..David<o:p></o:p></span></p></div></body></html>