---
name: "Bio::Ontology::Relationship"
section: "3pm"
platform: "linux"
package: "libbio-perl-perl"
version: "1.7.8-1"
release: "Debian 13 (Trixie)"
platforms: ["linux"]
url: "https://new.carta.tech/Bio::Ontology::Relationship"
---

# Bio::Ontology::Relationship(3pm)

a relationship for an ontology

## NAME

Bio::Ontology::Relationship - a relationship for an ontology

## SYNOPSIS

```
  $rel = Bio::Ontology::Relationship->new( -identifier     => "16847",
                                           -subject_term   => $subj,
                                           -object_term    => $obj,
                                           -predicate_term => $pred );
```

## DESCRIPTION

This is a basic implementation of Bio::Ontology::RelationshipI.

The terminology we use here is the one commonly used for ontologies, namely the triple of (subject, predicate, object), which in addition is scoped in a namespace (ontology). It is called triple because it is a tuple of three ontology terms.

There are other terminologies in use for expressing relationships. For those who it helps to better understand the concept, the triple of (child, relationship type, parent) would be equivalent to the terminology chosen here, disregarding the question whether the notion of parent and child is sensible in the context of the relationship type or not. Especially in the case of ontologies with a wide variety of predicates the parent/child terminology and similar ones can quickly become ambiguous (e.g., A synthesises B), meaningless (e.g., A binds B), or even conflicting (e.g., A is-parent-of B), and are therefore strongly discouraged.

## FEEDBACK

### Mailing Lists

User feedback is an integral part of the evolution of this and other Bioperl modules. Send your comments and suggestions preferably to the  Bioperl mailing lists  Your participation is much appreciated.

```
  bioperl-l@bioperl.org                  - General discussion
  http://bioperl.org/wiki/Mailing_lists  - About the mailing lists
```

### Support

Please direct usage questions or support issues to the mailing list:

*bioperl-l@bioperl.org*

rather than to the module maintainer directly. Many experienced and  reponsive experts will be able look at the problem and quickly  address it. Please include a thorough description of the problem  with code and data examples if at all possible.

### Reporting Bugs

Report bugs to the Bioperl bug tracking system to help us keep track the bugs and their resolution.  Bug reports can be submitted via the web:

```
  https://github.com/bioperl/bioperl-live/issues
```

## AUTHOR

Christian M. Zmasek

Email: czmasek-at-burnham.org  or  cmzmasek@yahoo.com

WWW:   http://monochrome-effect.net/

Address:

```
  Genomics Institute of the Novartis Research Foundation
  10675 John Jay Hopkins Drive
  San Diego, CA 92121
```

## CONTRIBUTORS

```
 Hilmar Lapp, email: hlapp at gmx.net
```

## APPENDIX

The rest of the documentation details each of the object methods. Internal methods are usually preceded with a \_

### new

```
 Title   : new
 Usage   : $rel = Bio::Ontology::Relationship->new(-identifier   => "16847",
                                                   -subject_term => $subject,
                                                   -object_term  => $object,
                                                   -predicate_term => $type );
 Function: Creates a new Bio::Ontology::Relationship.
 Returns : A new Bio::Ontology::Relationship object.
 Args    : -identifier     => the identifier of this relationship [scalar]
           -subject_term   => the subject term [Bio::Ontology::TermI]
           -object_term    => the object term [Bio::Ontology::TermI]
           -predicate_term => the predicate term [Bio::Ontology::TermI]
```

### init

```
 Title   : init()
 Usage   : $rel->init();
 Function: Initializes this Relationship to all undef.
 Returns :
 Args    :
```

### identifier

```
 Title   : identifier
 Usage   : $rel->identifier( "100050" );
           or
           print $rel->identifier();
 Function: Set/get for the identifier of this Relationship.
 Returns : The identifier [scalar].
 Args    : The identifier [scalar] (optional).
```

### subject\_term

```
 Title   : subject_term
 Usage   : $rel->subject_term( $subject );
           or
           $subject = $rel->subject_term();
 Function: Set/get for the subject term of this Relationship.
           The common convention for ontologies is to express
           relationships between terms as triples (subject, predicate,
           object).
 Returns : The subject term [Bio::Ontology::TermI].
 Args    : The subject term [Bio::Ontology::TermI] (optional).
```

### object\_term

```
 Title   : object_term
 Usage   : $rel->object_term( $object );
           or
           $object = $rel->object_term();
 Function: Set/get for the object term of this Relationship.
           The common convention for ontologies is to express
           relationships between terms as triples (subject, predicate,
           object).
 Returns : The object term [Bio::Ontology::TermI].
 Args    : The object term [Bio::Ontology::TermI] (optional).
```

### predicate\_term

```
 Title   : predicate_term
 Usage   : $rel->predicate_term( $type );
           or
           $type = $rel->predicate_term();
 Function: Set/get for the predicate (relationship type) of this
           relationship.
           The common convention for ontologies is to express
           relationships between terms as triples (subject, predicate,
           object).
 Returns : The predicate term [Bio::Ontology::TermI].
 Args    : The predicate term [Bio::Ontology::TermI] (optional).
```

### ontology

```
 Title   : ontology
 Usage   : $ont = $obj->ontology()
 Function: Get/set the ontology that defined this relationship.
 Example :
 Returns : an object implementing L<Bio::Ontology::OntologyI>
 Args    : on set, undef or an object implementing
           Bio::Ontology::OntologyI (optional)
```

See Bio::Ontology::OntologyI.

### to\_string

```
 Title   : to_string()
 Usage   : print $rel->to_string();
 Function: to_string method for Relationship.
 Returns : A string representation of this Relationship.
 Args    :
```

## Deprecated Methods

```
  These methods are deprecated and defined here solely to preserve
  backwards compatibility.
```
