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GH-134: Move Graph Comparison section to after 3.5 Triple Terms
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afs committed Jan 20, 2025
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Expand Up @@ -879,6 +879,39 @@ <h3>Triple Terms</h3>
as its <a>predicate</a>.</p>
</section>

<section id="graph-isomorphism">
<h3>Graph Comparison</h3>

<p id="section-graph-equality">Two
<a>RDF graphs</a> <var>G</var> and <var>G'</var> are
<dfn data-lt="graph isomorphism|isomorphic" data-lt-noDefault class="export">isomorphic</dfn>
(that is, they have an identical form)
if there is a bijection <var>M</var>
from the set of all <a>RDF terms</a> into that same set,
such that all of the following properties hold:</p>

<ul>
<li><var>M</var> maps blank nodes to blank nodes.</li>
<li><var>M</var>(<var>lit</var>)=<var>lit</var> for every <a>RDF literal</a> <var>lit</var>.</li>

<li><var>M</var>(<var>iri</var>)=<var>iri</var> for every <a>IRI</a> <var>iri</var>.</li>

<li><var>M</var>(<var>tt</var>) is the triple term ( <var>M</var>(<var>s</var>), <var>M</var>(<var>p</var>), <var>M</var>(<var>o</var>) ) if <var>tt</var> is a triple term of the form ( <var>s</var>, <var>p</var>, <var>o</var> ).</li>

<li>The triple ( <var>s</var>, <var>p</var>, <var>o</var> ) is in <var>G</var> if and
only if the triple ( <var>M</var>(<var>s</var>), <var>M</var>(<var>p</var>), <var>M</var>(<var>o</var>) ) is in
<var>G'</var>.</li>
</ul>

<p>See also: <a>IRI equality</a>, <a>literal term equality</a>.</p>

<p>With this definition, <var>M</var> shows how each blank node
in <var>G</var> can be replaced with
a new blank node to give <var>G'</var>. Graph isomorphism
is needed to support the RDF Test Cases [[RDF11-TESTCASES]] specification.</p>

</section>

<section id="section-text-direction" class="informative">
<h3>Initial Text Direction</h3>

Expand Down Expand Up @@ -953,44 +986,6 @@ <h3>Replacing Blank Nodes with IRIs</h3>
IRI that results in a well-known <a>URI</a> after IRI-to-URI mapping [[!RFC3987]].</p>
</section>

<section id="graph-isomorphism">
<h3>Graph Comparison</h3>

<p id="section-graph-equality">Two
<a>RDF graphs</a> <var>G</var> and <var>G'</var> are
<dfn data-lt="graph isomorphism|isomorphic" data-lt-noDefault class="export">isomorphic</dfn>
(that is, they have an identical form)
if there is a bijection <var>M</var>
from the set of all <a>RDF terms</a> into that same set,
such that all of the following properties hold:</p>

<ul>
<li><var>M</var> maps blank nodes to blank nodes.</li>
<li><var>M</var>(<var>lit</var>)=<var>lit</var> for every <a>RDF literal</a> <var>lit</var>.</li>

<li><var>M</var>(<var>iri</var>)=<var>iri</var> for every <a>IRI</a> <var>iri</var>.</li>

<li><var>M</var>(<var>tt</var>) is the triple term ( <var>M</var>(<var>s</var>), <var>M</var>(<var>p</var>), <var>M</var>(<var>o</var>) ) if <var>tt</var> is a triple term of the form ( <var>s</var>, <var>p</var>, <var>o</var> ).</li>

<li>The triple ( <var>s</var>, <var>p</var>, <var>o</var> ) is in <var>G</var> if and
only if the triple ( <var>M</var>(<var>s</var>), <var>M</var>(<var>p</var>), <var>M</var>(<var>o</var>) ) is in
<var>G'</var>.</li>
</ul>

<p>See also: <a>IRI equality</a>, <a>literal term equality</a>.</p>

<p>With this definition, <var>M</var> shows how each blank node
in <var>G</var> can be replaced with
a new blank node to give <var>G'</var>. Graph isomorphism
is needed to support the RDF Test Cases [[RDF11-TESTCASES]] specification.</p>

<div class="issue" data-number="128">
Graph isomorphism needs the following extra clause:
<ul>
<li>M(tt) is the triple term ( M(s), M(p), M(o) ) for tt a triple term of the form (s, p, o)</li>
</ul>
</div>
</section>
</section>

<section id="section-dataset">
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