add method for initializing/resetting equivalence graph

diff --git a/lib/Text/Tradition/Collation/RelationshipStore.pm b/lib/Text/Tradition/Collation/RelationshipStore.pm
index c7728cd..8ed2517 100644 (file)
--- a/lib/Text/Tradition/Collation/RelationshipStore.pm
+++ b/lib/Text/Tradition/Collation/RelationshipStore.pm
@@ -97,6 +97,7 @@ has 'equivalence_graph' => (
        is => 'ro',
        isa => 'Graph',
        default => sub { Graph->new() },
+       writer => '_reset_equivalence',
        );
        
 has '_node_equivalences' => (
@@ -1002,6 +1003,34 @@ sub _find_equiv_without {
        return keys %found;
 }
 
+=head2 rebuild_equivalence
+
+(Re)build the equivalence graph from scratch. Dumps the graph, makes a new one,
+adds all readings and edges, then makes an equivalence for all relationships.
+
+=cut
+
+sub rebuild_equivalence {
+       my $self = shift;
+       my $newgraph = Graph->new();
+       foreach my $r ( $self->collation->readings ) {
+               $newgraph->add_vertex( $r->id );
+       }
+       foreach my $e ( $self->collation->paths ) {
+               $newgraph->add_edge( @$e );
+       }
+       # Set this as the new equivalence graph
+       $self->_reset_equivalence( $newgraph );
+       
+       # Now collapse some nodes. This does no testing; it assumes that all
+       # preexisting relationships are valid.
+       foreach my $rel ( $self->relationships ) {
+               my $relobj = $self->get_relationship( $rel );
+               next unless $relobj && $relobj->colocated;
+               $self->_make_equivalence( @$rel );
+       }
+}
+
 ### Output logic
 
 sub _as_graphml {