XML Source

<source>
     <START1/>
     <END1/>
     <START2/>
     <END2/>
     <START3/>
     <END3/>
     <START4/>
     <END4/>
</source>

Graphotron Source

<graphotron xmlns:daVinci="http://zvon.org/graphotron/daVinci" xmlns="http://zvon.org/graphotron" >
     <vertex match="/*/*">
          <name select="name()"/>
     </vertex>
     <edge match="/*/START1" select="/*/END1">
          <daVinci:_DIR>normal</daVinci:_DIR>
     </edge>
     <edge match="/*/START2" select="/*/END2">
          <daVinci:_DIR>inverse</daVinci:_DIR>
     </edge>
     <edge match="/*/START3" select="/*/END3">
          <daVinci:_DIR>both</daVinci:_DIR>
     </edge>
     <edge match="/*/START4" select="/*/END4">
          <daVinci:_DIR>none</daVinci:_DIR>
     </edge>
</graphotron>