Provided by: libbio-perl-perl_1.7.2-2_all 
NAME
Bio::DB::SeqFeature -- Normalized feature for use with Bio::DB::SeqFeature::Store
SYNOPSIS
use Bio::DB::SeqFeature::Store;
# Open the sequence database
my $db = Bio::DB::SeqFeature::Store->new( -adaptor => 'DBI::mysql',
-dsn => 'dbi:mysql:test');
my ($feature) = $db->get_features_by_name('ZK909');
my @subfeatures = $feature->get_SeqFeatures();
my @exons_only = $feature->get_SeqFeatures('exon');
# create a new object
my $new = $db->new_feature(-primary_tag=>'gene',
-seq_id => 'chr3',
-start => 10000,
-end => 11000);
# add a new exon
$feature->add_SeqFeature($db->new_feature(-primary_tag=>'exon',
-seq_id => 'chr3',
-start => 5000,
-end => 5551));
DESCRIPTION
The Bio::DB::SeqFeature object is the default SeqFeature class stored in
Bio::DB::SeqFeature databases. It implements both the
Bio::DB::SeqFeature::NormalizedFeatureI and Bio::DB::SeqFeature::NormalizedTableFeatureI
interfaces, which means that its subfeatures, if any, are stored in the database in a
normalized fashion, and that the parent/child hierarchy of features and subfeatures are
also stored in the database as set of tuples. This provides efficiencies in both storage
and retrieval speed.
Typically you will not create Bio::DB::SeqFeature directly, but will ask the database to
do so on your behalf, as described in Bio::DB::SeqFeature::Store.
new
Title : new
Usage : $feature = Bio::DB::SeqFeature::NormalizedFeature->new(@args)
Function: create a new feature
Returns : the new seqfeature
Args : see below
Status : public
This method creates and, if possible stores into a database, a new
Bio::DB::SeqFeature::NormalizedFeature object using the specialized Bio::DB::SeqFeature
class.
The arguments are the same to Bio::SeqFeature::Generic->new() and
Bio::Graphics::Feature->new(). The most important difference is the -store option, which
if present creates the object in a Bio::DB::SeqFeature::Store database, and the -index
option, which controls whether the feature will be indexed for retrieval (default is
true). Ordinarily, you would only want to turn indexing on when creating top level
features, and off only when storing subfeatures. The default is on.
Arguments are as follows:
-seq_id the reference sequence
-start the start position of the feature
-end the stop position of the feature
-display_name the feature name (returned by seqname)
-primary_tag the feature type (returned by primary_tag)
-source the source tag
-score the feature score (for GFF compatibility)
-desc a description of the feature
-segments a list of subfeatures (see Bio::Graphics::Feature)
-subtype the type to use when creating subfeatures
-strand the strand of the feature (one of -1, 0 or +1)
-phase the phase of the feature (0..2)
-url a URL to link to when rendered with Bio::Graphics
-attributes a hashref of tag value attributes, in which the key is the tag
and the value is an array reference of values
-store a previously-opened Bio::DB::SeqFeature::Store object
-index index this feature if true
Aliases:
-id an alias for -display_name
-seqname an alias for -display_name
-display_id an alias for -display_name
-name an alias for -display_name
-stop an alias for end
-type an alias for primary_tag
Bio::SeqFeatureI methods
The following Bio::SeqFeatureI methods are supported:
seq_id(), start(), end(), strand(), get_SeqFeatures(),
display_name(), primary_tag(), source_tag(), seq(),
location(), primary_id(), overlaps(), contains(), equals(),
intersection(), union(), has_tag(), remove_tag(),
add_tag_value(), get_tag_values(), get_all_tags()
Some methods that do not make sense in the context of a genome annotation database system,
such as attach_seq(), are not supported.
Please see Bio::SeqFeatureI for more details.
add_SeqFeature
Title : add_SeqFeature
Usage : $flag = $feature->add_SeqFeature(@features)
Function: Add subfeatures to the feature
Returns : true if successful
Args : list of Bio::SeqFeatureI objects
Status : public
Add one or more subfeatures to the feature. For best results, subfeatures should be of the
same class as the parent feature (i.e. do not try mixing
Bio::DB::SeqFeature::NormalizedFeature with other feature types).
An alias for this method is add_segment().
update
Title : update
Usage : $flag = $feature->update()
Function: Update feature in the database
Returns : true if successful
Args : none
Status : public
After changing any fields in the feature, call update() to write it to the database. This
is not needed for add_SeqFeature() as update() is invoked automatically.
get_SeqFeatures
Title : get_SeqFeature
Usage : @subfeatures = $feature->get_SeqFeatures([@types])
Function: return subfeatures of this feature
Returns : list of subfeatures
Args : list of subfeature primary_tags (optional)
Status : public
This method extends the Bio::SeqFeatureI get_SeqFeatures() slightly by allowing you to
pass a list of primary_tags, in which case only subfeatures whose primary_tag is contained
on the list will be returned. Without any types passed all subfeatures are returned.
object_store
Title : object_store
Usage : $store = $feature->object_store([$new_store])
Function: get or set the database handle
Returns : current database handle
Args : new database handle (optional)
Status : public
This method will get or set the Bio::DB::SeqFeature::Store object that is associated with
the feature. After changing the store, you should probably unset the primary_id() of the
feature and call update() to ensure that the object is written into the database as a new
feature.
overloaded_names
Title : overloaded_names
Usage : $overload = $feature->overloaded_names([$new_overload])
Function: get or set overloading of object strings
Returns : current flag
Args : new flag (optional)
Status : public
For convenience, when objects of this class are stringified, they are represented in the
form "primary_tag(display_name)". To turn this feature off, call overloaded_names() with a
false value. You can invoke this on an individual feature object or on the class:
Bio::DB::SeqFeature::NormalizedFeature->overloaded_names(0);
segment
Title : segment
Usage : $segment = $feature->segment
Function: return a Segment object corresponding to feature
Returns : a Bio::DB::SeqFeature::Segment
Args : none
Status : public
This turns the feature into a Bio::DB::SeqFeature::Segment object, which you can then use
to query for overlapping features. See Bio::DB::SeqFeature::Segment.
AUTOLOADED methods
@subfeatures = $feature->Exon;
If you use an unknown method that begins with a capital letter, then the feature
autogenerates a call to get_SeqFeatures() using the lower-cased method name as the
primary_tag. In other words $feature->Exon is equivalent to:
@subfeature s= $feature->get_SeqFeatures('exon')
load_id
Title : load_id
Usage : $id = $feature->load_id
Function: get the GFF3 load ID
Returns : the GFF3 load ID (string)
Args : none
Status : public
For features that were originally loaded by the GFF3 loader, this method returns the GFF3
load ID. This method may not be supported in future versions of the module.
primary_id
Title : primary_id
Usage : $id = $feature->primary_id([$new_id])
Function: get/set the database ID of the feature
Returns : the current primary ID
Args : none
Status : public
This method gets or sets the primary ID of the feature in the underlying
Bio::DB::SeqFeature::Store database. If you change this field and then call update(), it
will have the effect of making a copy of the feature in the database under a new ID.
target
Title : target
Usage : $segment = $feature->target
Function: return the segment correspondent to the "Target" attribute
Returns : a Bio::DB::SeqFeature::Segment object
Args : none
Status : public
For features that are aligned with others via the GFF3 Target attribute, this returns a
segment corresponding to the aligned region. The CIGAR gap string is not yet supported.
Internal methods
$feature->as_string()
Internal method used to implement overloaded stringification.
$boolean = $feature->type_match(@list_of_types)
Internal method that will return true if the primary_tag of the feature and source_tag
match any of the list of types (in primary_tag:source_tag format) provided.
BUGS
This is an early version, so there are certainly some bugs. Please use the BioPerl bug
tracking system to report bugs.
SEE ALSO
bioperl, Bio::DB::SeqFeature::Store, Bio::DB::SeqFeature::Segment,
Bio::DB::SeqFeature::NormalizedFeature, Bio::DB::SeqFeature::GFF3Loader,
Bio::DB::SeqFeature::Store::DBI::mysql, Bio::DB::SeqFeature::Store::bdb
AUTHOR
Lincoln Stein <lstein@cshl.org>.
Copyright (c) 2006 Cold Spring Harbor Laboratory.
This library is free software; you can redistribute it and/or modify it under the same
terms as Perl itself.