Provided by: libgo-perl_0.15-6_all bug

NAME

       GO::Model::Graph    - a collection of relationships over terms

SYNOPSIS

         # FETCHING GRAPH FROM FILES
         use GO::Parser;
         my $parser = new GO::Parser({handler=>'obj'});
         $parser->parse("gene_ontology.obo");     # ontology
         $parser->parse("gene-associations.sgd"); # gene assocs
         # get L<GO::Model::Graph> object
         my $graph = $parser->handler->graph;
         my $terms = $graph->term_query("/transmembrane/");  # matching terms
         foreach my $term (@$terms) {
           # find gene products associated to this term
           my $assocs = $graph->deep_association_list($term->acc);
           printf "Term: %s %s\n", $term->acc, $term->name;
           print "  Associations (direct and via transitive closure_\n";
           foreach my $assoc (@$assocs) {
             next if $assoc->is_not;
             printf "  Assoc evidence: %s to: %s %s\n",
               join(';', map {$_->code} @{$assoc->evidence_list}),
               $assoc->gene_product->xref->as_str,
               $assoc->gene_product->symbol;
           }
         }

         # -- alternatively, use this code... --

         # FETCHING FROM DATABASE (requires go-db-perl library)
         # pretty-printing a subgraph from "nuclear pore"
         $apph = GO::AppHandle->connect(-dbname=>"$dbname");
         $term = $apph->get_term({name=>"nuclear pore"});
         $graph =
                 $apph->get_graph_by_terms([$term], $depth);

         $it = $graph->create_iterator;
         # returns a GO::Model::GraphIterator object

         while (my $ni = $it->next_node_instance) {
           $depth = $ni->depth;
           $term = $ni->term;
           $reltype = $ni->parent_rel->type;
           printf
             "%s %8s Term = %s (%s)  // number_of_association=%s // depth=%d\n",
                 "----" x $depth,
                 $reltype,
                 $term->name,
                 $term->public_acc,
                 $term->n_associations || 0,
                 $depth;
         }

DESCRIPTION

       Object containing Nodes (GO::Model::Term objects) and relationships
       (:<GO::Model::Relationship> objects)

       this may be either the whole ontology tree, or a subgraph, depending on how the object is
       instantiated.

   ONTOLOGY GRAPH MODEL
       relationships can be thought of as statements or sentences of the form

         SUBJECT-TERM PREDICATE OBJECT-TERM

       for example,

         "dog" IS_A "animal"

         "G-Protein coupled receptor" IS_A "transmembrane receptor"

       Statements have a subject (i.e. the subject of the sentence/statement), a
       predicate/relationship-type and an object (i.e. the object of the sentence/statement)

       Relationships can also be seen as arcs in a directed graph, with the subject being
       equivalent to the child, and the object equivalent to the parent. The arc is labeled with
       the predicate/relationship-type.

       perl doesn't handle bidirectional links between objects too well, so rather than having
       the relationship object know about the terms or the term know about the realtionships, all
       the graph info is in the Graph object

       the Relationship object gives you the accessions of the related terms, use the Graph
       methods to fetch these actual terms.

       The idea is to keep the Term & Relationship objects lightweight, and keep the Graph logic
       in the Graph object. The Graph object is responsible for stuff like making sure that a
       Term object is not instantiated twice if it can be reached by two different paths.

       Currently all graphs are acyclic, cyclic graphs may be allowed in the future when such
       relationships are added to GO/OBOA

   TRANSITIVE CLOSURES
        graph object will calculate transitive closures for you - that is it
       will follow the path in the graph to the root or to all leafs

   ITERATORS
       Using the create_iterator and iterate methods, you can create "visitors" that will
       traverse the graph, performing actions along the way. Functional-style programming is
       encouraged, as the iterature() method allows for the passing of lexical closures:

         $graph->iterate(sub {$term=shift->term;
                              printf "%s %s\n", $term->acc,$term->name},
                         {direction=>'up',
                          acc=>"GO:0008045"})

   SEE ALSO
       go-perl GO::Model::Term GO::Parser GO::AppHandle

   new
         Usage   - $g = GO::Model::Graph->new;
         Returns - GO::Model::Graph;
         Args    -

       Normally you would not create a graph object yourself - this is typically done for you by
       either a GO::Parser object or a GO::AppHandle object

   create_iterator
         Usage   - $it = $graph->create_iterator("GO:0003677")
         Usage   - $it = $graph->create_iterator({acc=>"GO:0008045",
                                                  direction=>"up"});
         Returns - GO::Model::GraphIterator;
         Args    - accession no [optional] or GO::Model::Term [optional]

       makes a GO::Model::GraphIterator, an object which traverses the graph

   iterate
         Usage   - $graph->iterate(sub {$ni=shift;printf "%s\n", $ni->term->name});
         Usage   - sub mysub {...}; $graph->iterate(\&mysub);
         Returns -
         Args    -  CODE

       iterates through the graph executing CODE on every GO::Model::GraphNodeInstance object

   term_filter
         Alias   - node_filter
         Usage   - $terms =
                      $graph->term_filter(sub {shift->term->name =~ /transmembrane/});
         Usage   - sub mysub {...}; $graph->iterate(\&mysub);
         Returns -   ref to an array of GO::Model::Term objects
         Args    -  CODE

       iterates through the graph executing CODE on every GO::Model::GraphNodeInstance object. If
       CODE returns true, that node will be returned

   term_query
         Usage   - $terms = $graph->term_query({name=>'/transmembrane/'});
         Usage   - $terms = $graph->term_query({acc=>'GO:0008045'});
         Usage   - $terms = $graph->term_query('/transmembrane/');
         Returns - ref to an array of GO::Model::Term objects
         Args    - hashref of constraints
                   OR name constraint as string

       returns a set of terms matching query constraints. If the constraint value is enclosed in
       // a regexp match will be performed

       constraints are ANDed. For more complex queries, use node_filter()

   subgraph
         Usage   - my $subgraph = $graph->subgraph({acc=>"GO:0008045"});
         Returns - GO::Model::Graph
         Args    - as term_query()

       creates a subgraph of the current graph containing the terms returned by a term_query()
       call and all paths to the root

   subgraph_by_terms
         Usage   - my $subgraph = $graph->subgraph_by_terms($terms);
         Usage   - my $subgraph = $graph->subgraph_by_terms($terms,{partial=>1});
         Returns - GO::Model::Graph
         Args    - GO::Model::Term listref

       creates a subgraph of the current graph containing the specified terms

       The path-to-top will be calculated for all terms and added to the subgraph, UNLESS the
       partial option is set; in this case a relationship between

   get_all_nodes
         Usage   - my $node_listref = $graph->get_all_nodes();
         Synonyms- get_all_terms
         Returns - ref to an array of GO::Model::Term objects
         Args    - none

       The returned array is UNORDERED

       If you want the returned list ordered (eg breadth first or depth first) use the
       create_iterator() method to get a GO::Model::GraphIterator

       See also GO::Model::Term

   get_term
         Usage   - my $term = $graph->get_term($acc);
         Synonyms- get_node
         Returns - GO::Model::Term
         Args    - id

         returns a GO::Model::Term object for an accession no.
         the term must be in the Graph object

       See also GO::Model::Term

   get_term_by_name
         Usage   - my $term = $graph->get_term_by_name("blah");
         Returns - GO::Model::Term
         Args    - string

         returns a GO::Model::Term object for a name
         the term must be in the Graph object

       CASE INSENSITIVE

       See also GO::Model::Term

   get_terms_by_subset
         Usage   - my $term = $graph->get_terms_by_subset("goslim_plant");
         Returns - GO::Model::Term
         Args    - string

         returns a GO::Model::Term object for a subset
         the term must be in the Graph object

       CASE INSENSITIVE

       See also GO::Model::Term

   get_top_nodes
         Usage   - my $node_listref = $graph->get_top_nodes();
         Synonyms- get_top_terms
         Returns - ref to an array of GO::Model::Term objects
         Args    - none

       usually returns 1 node - the root term

       See also GO::Model::Term

   get_leaf_nodes
         Usage   - my $node_listref = $graph->get_top_nodes();
         Synonyms- get_leaf_terms
         Returns - ref to an array of GO::Model::Term objects
         Args    - none

       See also GO::Model::Term

   is_leaf_node
         Usage   - if ($graph->is_leaf_node($acc)) {...}
         Returns - bool
         Args    - accession str

       See also GO::Model::Term

   seed_nodes
         Usage   - $nodes = $graph->seed_nodes;
         Returns - GO::Model::Term listref
         Args    - GO::Model::Term listref [optional]

       gets/sets the "seed" nodes/terms - these are the terms the Graph is started from, e.g. for
       building a node ancestory graph, the seed term would be the leaf of this graph, but not
       term that are expanded or collpased from the ancestory graph.

       This is mostly relevant if you are fetching your graphs from a database via go-db-perl

       See also GO::Model::Term

   focus_nodes
         Usage   - $nodes = $graph->focus_nodes;
         Synonyms- focus_terms
         Returns - GO::Model::Term listref
         Args    - GO::Model::Term listref [optional]

       gets/sets the "focus" nodes/terms - these are the terms the Graph is centred around; for
       instance, if the graph was built around a query to "endoplasmic*" all the terms matching
       this string would be focused

       This is mostly relevant if you are fetching your graphs from a database via go-db-perl

       See also GO::Model::Term

   is_focus_node
         Usage   - if ($g->is_focus_node($term)) {..}
         Returns - bool
         Args    - GO::Model::Term

   add_focus_node
         Usage   - $g->add_focus_node($term)
         Returns -
         Args    - GO::Model::Term

       See also GO::Model::Term

   paths_to_top
         Usage   - my $paths = $graph->paths_to_top("GO:0005045");
         Returns - arrayref of GO::Model::Path objects
         Args    -

       See also GO::Model::Path

   node_count
         Usage   - my $count = $g->node_count
         Synonyms- term_count
         Returns - int
         Args    -

       returns the number of terms/nodes in the graph

       See also GO::Model::Term

   n_associations
         Usage   - my $count = $g->n_associations($acc);
         Returns - int
         Args    -

       if you parsed an association file into this graph, this will return the number of
       instances attached directly to acc

       See also GO::Model::Association See also GO::Model::GeneProduct

   n_deep_associations
         Usage   - my $count = $g->n_deep_associations($acc);
         Returns - int
         Args    -

       if you parsed an association file into this graph, this will return the number of
       instances attached directly to acc OR to a node subsumed by acc

       See also GO::Model::Association See also GO::Model::GeneProduct

   n_children
         Usage   - $n = $graph->n_children('GO:0003677');
         Synonyms- n_sterms, n_subj_terms, n_subject_terms
         Returns - int
         Args    -

       returns the number of DIRECT children/subject/subordinate terms beneath this one

   n_parents
         Usage   - $n = $graph->n_parents(3677);
         Synonyms- n_oterms, n_obj_terms, n_object_terms
         Returns - int
         Args    -

       returns the number of DIRECT parent/object/superordinate terms above this one

   association_list
         Usage   - $assocs = $g->association_list('GO:0003677')
         Returns - listref of GO::Model::Association
         Args    - acc (string)

       returns a list of association objects directly attached to the specified term

       See also GO::Model::Association

   get_direct_associations
         Usage   -
         Returns -
         Args    -

       See also GO::Model::Association

   deep_association_list
         Usage   - $assocs = $g->association_list('GO:0003677')
         Returns - listref of GO::Model::Association
         Args    - acc (string)

       returns a list of association objects directly and indirectly attached to the specified
       term. (ie assocs attached to the term or to terms subsumed by the specified term).

       See also GO::Model::Association

   product_list
         Usage   - $prods = $g->product_list('GO:0003677')
         Returns - listref of GO::Model::GeneProduct
         Args    - acc (string)

       returns a list of distinct gene product objects directly attached to the specified term.

       See also GO::Model::GeneProduct

   deep_product_list
         Usage   - $prods = $g->deep_product_list('GO:0003677')
         Returns - listref of GO::Model::GeneProduct
         Args    - acc (string)

       returns a list of distinct gene product objects directly and indirectly attached to the
       specified term. (ie assocs attached to the term or to terms subsumed by the specified
       term).

       See also GO::Model::GeneProduct

   deep_product_count
         Usage   - $n_prods = $g->deep_product_count('GO:0003677')
         Returns - int
         Args    - acc (string)

       returns a count of distinct gene product objects directly and indirectly attached to the
       specified term. performs transitive closure. will not count gene products twice

       See also GO::Model::GeneProduct

   get_relationships
         Usage   - my $rel_listref = $graph->get_relationships('GO:0003677');
         Returns - ref to an array of GO::Model::Relationship objects
         Args    - identifier/acc (string)

       returns relationships which concern the specified term; the specified term can be the
       subject or object term in the relationship (ie child or parent)

       See also GO::Model::Relationship

   get_parent_relationships
         Usage   - my $rel_listref = $graph->get_parent_relationships('GO:0003677');
         Synonym - get_relationships_by_child
         Synonym - get_relationships_by_subj
         Synonym - get_relationships_by_subject
         Synonym - get_obj_relationships
         Synonym - get_object_relationships
         Returns - ref to an array of GO::Model::Relationship objects
         Args    - identifier/acc (string)

       See also GO::Model::Relationship

   get_child_relationships
         Usage   - my $rel_listref = $graph->get_child_relationships('GO:0003677');
         Synonym - get_relationships_by_parent
         Synonym - get_relationships_by_obj
         Synonym - get_relationships_by_object
         Synonym - get_subj_relationships
         Synonym - get_subject_relationships
         Returns - ref to an array of GO::Model::Relationship objects
         Args    - identifier/acc (string)

       See also GO::Model::Relationship

   get_all_relationships
         Usage   -
         Returns - GO::Model::Relationship list
         Args    -

       returns all the relationships/statements in this graph

       See also GO::Model::Relationship

   get_parent_terms
         Usage   - my $term_lref = $graph->get_parent_terms($parent_term->acc);
         Synonym - get_obj_terms
         Synonym - get_object_terms
         Returns - ref to array of GO::Model::Term objs
         Args    - the accession of the query term

       See also GO::Model::Term

   get_parent_terms_by_type
         Usage   -
         Synonym - get_obj_terms_by_type
         Synonym - get_object_terms_by_type
         Returns - ref to array of GO::Model::Term objs
         Args    - the accession of the query term
                 - the type by which to constrain relationships

       See also GO::Model::Term

   get_recursive_parent_terms
        Title   : get_recursive_parent_terms
        Usage   :
        Synonyms: get_recursive_obj_terms
        Synonyms: get_recursive_object_terms
        Function:
        Example :
        Returns :
        Args    : accession of query term

       See also GO::Model::Term

   get_recursive_parent_terms_by_type
        Title   : get_recursive_parent_terms_by_type
        Usage   :
        Synonyms: get_recursive_obj_terms_by_type
        Synonyms: get_recursive_object_terms_by_type
        Function:
        Example :
        Returns :
        Args    :

       if type is blank, gets all

       See also GO::Model::Term

   get_reflexive_parent_terms
        Title   : get_reflexive_parent_terms
        Usage   :
        Function:
        Example :
        Returns :
        Args    : acc

       returns parent terms plus the term (for acc) itself

       [reflexive transitive closure of relationships in upward direction]

       See also GO::Model::Term

   get_reflexive_parent_terms_by_type
        Title   : get_reflexive_parent_terms_by_type
        Usage   :
        Function:
        Example :
        Returns : listref of terms
        Args    : acc, type

       closure of relationship including the term itself

       See also GO::Model::Term

   get_child_terms
         Usage   - my $term_lref = $graph->get_child_terms($parent_term->acc);
         Synonym - get_subj_terms
         Synonym - get_subject_terms
         Returns - ref to array of GO::Model::Term objs
         Args    -

       See also GO::Model::Term

   get_child_terms_by_type
         Synonym - get_subj_terms_by_type
         Synonym - get_subject_terms_by_type
         Returns - ref to array of GO::Model::Term objs
         Args    - the accession of the query term
                 - the type by which to constrain relationships

       See also GO::Model::Term

   get_recursive_child_terms
        Title   : get_recursive_child_terms
        Usage   :
        Synonyms: get_recursive_subj_terms
        Synonyms: get_recursive_subject_terms
        Function:
        Example :
        Returns : a reference to an array of L<GO::Model::Term> objects
        Args    : the accession of the query term

       See also GO::Model::Term

   get_recursive_child_terms_by_type
        Title   : get_recursive_child_terms_by_type
        Usage   :
        Synonyms: get_recursive_subj_terms_by_type
        Synonyms: get_recursive_subject_terms_by_type
        Function:
        Example :
        Returns : a reference to an array of L<GO::Model::Term> objects
        Args    : accession, type

       if type is blank, gets all

       See also GO::Model::Term

   _get_recursive_related_terms_by_type
        Title   : _get_recursive_related_terms_by_type
        Usage   :
        Function: Obtain all relationships of the given kind and type for the
                  term identified by its accession, and recursively repeat
                  this with all parents and children as query for parent and
                  child relationships, respectively.

                  This is an internal method.
        Example :
        Returns : A reference to an array of L<GO::Model::Term> objects.
        Args    : - the kind of relationship, either "child" or "parent"
                  - the accession of the term with which to query
                  - the type to which to constrain relationships (optional,
                    all types if left undef)
                  - TRUE if reflexive and FALSE otherwise (default FALSE)

       See also GO::Model::Term

   _get_related_terms_by_type
         Usage   - my $term_lref = $graph->_get_related_terms_by_type("child",$acc);
         Returns - ref to array of GO::Model::Term objs

         Args    - the kind of relationship, either "child" or "parent"
                 - the accession of the term for which to obtain rel.ships
                 - the type by which to constrain relationships (optional,
                   defaults to all terms if left undef)

       This is an internal method.

   get_parent_accs_by_type
         Usage   -
         Returns -
         Args    - acc, type

   get_reflexive_parent_accs_by_type
        Title   : get_reflexive_parent_accs_by_type
        Usage   :
        Function:
        Example :
        Returns : listref of terms
        Args    : acc, type

       closure of relationship including the term itself

       See also GO::Model::Term

   get_relationships_between_terms
        Title   : get_relationships_between_terms
        Usage   :
        Function:
        Example :
        Returns : [] of relationships
        Args    : parent id, child id

       See also GO::Model::Relationship

   get_parent_closure_hash_by_type
        Title   : get_parent_closure_hash_by_type
        Usage   :
        Function: given a term-acc and relationship type, will give a hash that
                  can be used to check if a term X is a parent of term Y
        Example :
        Returns :
        Args    :

       keys will be lower-cased

   add_child_relationship
       See also GO::Model::Relationship

   add_parent_relationship
           parent relationships are as valued as child relationships

       See also GO::Model::Relationship

   close_below
         Usage   - $graph->close_below(3677);
         Returns -
         Args    - term (as acc or GO::Model::Term object)

       gets rid of everything below a node

       used by AmiGO for when a user closes a term in the graph

   find_roots
         Usage   - my $terms = $graph->find_roots;
         Returns - arrayref of GO::Model::Term objects
         Args    -

       All terms withOUT a parent

       See also GO::Model::Term

   get_all_products
         Usage   -
         Returns -
         Args    -

       See also GO::Model::GeneProduct

   merge
        Usage   - $g->merge($g2);
        Returns -
        Args    - GO::Model::Graph

       merges two graphs

   export
         Usage   - $graph->export({format=>$format});
         Returns -
         Args    - opt hash

       writes out the graph in any export format, including obo, go_ont, owl, png (graphviz) etc

   to_xml
         Usage   -
         Returns -
         Args    -

   add_term
        Usage   - $g->add_term($term)
        Returns -
        Args    - GO::Model::Term

   add_node
         Usage   -
         Returns -
         Args    -

       synonym for add_term

   add_relationship
         Usage   - $graph->add_relationship({acc1=>from_id, acc2=>to_id});
         Usage   - $graph->add_relationship($from_id, $to_id, $type});
         Usage   - $graph->add_relationship($obj, $subj, $type});
         Returns -
         Args    -

       only one relationship between id1 and id2 is allowed

       See also GO::Model::Relationship

   add_buckets
        Usage   -
        Returns -
        Args    -

       adds bucket terms to non-leaf nodes

       this is useful for making GO slims

   to_text_output
         Usage   -
         Returns -
         Args    - fmt, assocs [bool]

       hacky text output

       this method should probably move out of the model code into output adapters