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Text Encoding Initiative

The XML Version of the TEI Guidelines

<arc>

<arc> encodes an arc, the connection from one node to another in a graph.
Attributes (In addition to global attributes)
label gives a label for an arc.
Datatype: CDATA
Values: A character string.
Default: #IMPLIED
label2 gives a second label for an arc.
Datatype: CDATA
Values: A character string.
Default: #IMPLIED
Note

Use this attribute together with the label attribute if a transducer is being encoded.
from gives the identifier of the node which is adjacent from this arc.
Datatype: IDREF
Values: The identifier of a node.
Default: #REQUIRED
to gives the identifier of the node which is adjacent to this arc.
Datatype: IDREF
Values: The identifier of a node.
Default: #REQUIRED
Example 
<arc label="OLD" label2="VIEUX" from="t3" to="t3"/>
Note

The <arc> element must be used if the arcs are labeled. Otherwise, arcs can be encoded using the adj, adjTo and adjFrom attributes on the <node> tags in the graph. Both <arc> tags and adjacency attributes can be used, but the resulting encoding would be highly redundant.
Module Declared in file teinet2; Additional tag set for Graph Theory: enabled by TEI.nets
Data Description empty
May occur within graph
Declaration 
<!ELEMENT arc %om.RO; EMPTY> 
<!ATTLIST arc  
      %a.global;
      label CDATA #IMPLIED
      label2 CDATA #IMPLIED
      from IDREF #REQUIRED
      to IDREF #REQUIRED>
See further 21.1 Graphs and Digraphs

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