Skip to content


Subversion checkout URL

You can clone with HTTPS or Subversion.

Download ZIP
tree: 09f5ae8034
Fetching contributors…

Cannot retrieve contributors at this time

511 lines (387 sloc) 14.064 kb
# bioperl module for Bio::PrimaryQual
# Please direct questions and support issues to <>
# Cared for by Chad Matsalla <>
# Copyright Chad Matsalla
# You may distribute this module under the same terms as perl itself
# POD documentation - main docs before the code
=head1 NAME
Bio::Seq::PrimaryQual - Bioperl lightweight Quality Object
use Bio::Seq::PrimaryQual;
# you can use either a space-delimited string for quality
my $string_quals = "10 20 30 40 50 40 30 20 10";
my $qualobj = Bio::Seq::PrimaryQual->new(
-qual => $string_quals,
-id => 'QualityFragment-12',
-accession_number => 'X78121',
# _or_ you can use an array of quality values
my @q2 = split/ /,$string_quals;
$qualobj = Bio::Seq::PrimaryQual->new(
-qual => \@q2,
-primary_id => 'chads primary_id',
-desc => 'chads desc',
-accession_number => 'chads accession_number',
-id => 'chads id'
# to get the quality values out:
my @quals = @{$qualobj->qual()};
# to give _new_ quality values
my $newqualstring = "50 90 1000 20 12 0 0";
This module provides a mechanism for storing quality
values. Much more useful as part of
Bio::Seq::SeqWithQuality where these quality values
are associated with the sequence information.
=head2 Mailing Lists
User feedback is an integral part of the evolution of this and other
Bioperl modules. Send your comments and suggestions preferably to one
of the Bioperl mailing lists. Your participation is much appreciated. - General discussion - About the mailing lists
=head2 Support
Please direct usage questions or support issues to the mailing list:
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.
=head2 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
=head1 AUTHOR - Chad Matsalla
The rest of the documentation details each of the object methods. Internal methods are usually preceded with a _
package Bio::Seq::PrimaryQual;
use strict;
use base qw(Bio::Root::Root Bio::Seq::QualI);
our $MATCHPATTERN = '0-9eE\.\s+-';
=head2 new()
Title : new()
Usage : $qual = Bio::Seq::PrimaryQual->new(
-qual => '10 20 30 40 50 50 20 10',
-id => 'human_id',
-accession_number => 'AL000012',
Function: Returns a new Bio::Seq::PrimaryQual object from basic
constructors, being a string _or_ a reference to an array for the
sequence and strings for id and accession_number. Note that you
can provide an empty quality string.
Returns : a new Bio::Seq::PrimaryQual object
sub new {
my ($class, @args) = @_;
my $self = $class->SUPER::new(@args);
# default: turn ON the warnings (duh)
my($qual,$id,$acc,$pid,$desc,$given_id,$header) =
if( defined $id && defined $given_id ) {
if( $id ne $given_id ) {
$self->throw("Provided both id and display_id constructor functions. [$id] [$given_id]");
if( defined $given_id ) { $id = $given_id; }
# note: the sequence string may be empty
$self->qual(defined($qual) ? $qual : []);
$header && $self->header($header);
$id && $self->display_id($id);
$acc && $self->accession_number($acc);
$pid && $self->primary_id($pid);
$desc && $self->desc($desc);
return $self;
=head2 qual()
Title : qual()
Usage : @quality_values = @{$obj->qual()};
Function: Get or set the quality as a reference to an array containing the
quality values. An error is generated if the quality scores are
invalid, see validate_qual().
Returns : A reference to an array.
sub qual {
my ($self,$value) = @_;
if( ! defined $value || length($value) == 0 ) {
$self->{'qual'} ||= [];
} elsif( ref($value) =~ /ARRAY/i ) {
# if the user passed in a reference to an array
$self->{'qual'} = $value;
} else {
$self->validate_qual($value, 1);
$value =~ s/^\s+//;
$self->{'qual'} = [split(/\s+/,$value)];
return $self->{'qual'};
=head2 seq()
Title : seq()
Usager : $sequence = $obj->seq();
Function : Returns the quality numbers as a space-separated string.
Returns : Single string.
Args : None.
sub seq {
return join ' ', @{ shift->qual };
=head2 validate_qual($qualstring)
Title : validate_qual($qualstring)
Usage : print("Valid.") if { &validate_qual($self, $quality_string); }
Function: Test that the given quality string is valid. It is expected to
contain space-delimited numbers that can be parsed using split /\d+/.
However, this validation takes shortcuts and only tests that the
string contains characters valid in numbers: 0-9 . eE +-
Note that empty quality strings are valid too.
Returns : 1 for a valid sequence, 0 otherwise
Args : - Scalar containing the quality string to validate.
- Boolean to optionally throw an error if validation failed
sub validate_qual {
my ($self, $qualstr, $throw) = @_;
if ( (defined $qualstr ) &&
($qualstr !~ /^[$MATCHPATTERN]*$/) ) {
if ($throw) {
$self->throw("Failed validation of quality score from '".
(defined($self->id)||'[unidentified sequence]')."'. No numeric ".
"value found.\n");
return 0;
return 1;
=head2 subqual($start,$end)
Title : subqual($start,$end)
Usage : @subset_of_quality_values = @{$obj->subqual(10,40)};
Function: returns the quality values from $start to $end, where the
first value is 1 and the number is inclusive, ie 1-2 are the
first two bases of the sequence. Start cannot be larger than
end but can be equal.
Returns : A reference to an array.
Args : a start position and an end position
sub subqual {
my ($self,$start,$end) = @_;
if( $start > $end ){
$self->throw("in subqual, start [$start] has to be greater than end [$end]");
if( $start <= 0 || $end > $self->length ) {
$self->throw("You have to have start positive and length less than the total length of sequence [$start:$end] Total ".$self->length."");
# remove one from start, and then length is end-start
my @sub_qual_array = @{$self->{qual}}[$start..$end];
# return substr $self->seq(), $start, ($end-$start);
return \@sub_qual_array;
=head2 display_id()
Title : display_id()
Usage : $id_string = $obj->display_id();
Function: returns the display id, aka the common name of the Quality
The semantics of this is that it is the most likely string to be
used as an identifier of the quality sequence, and likely to have
"human" readability. The id is equivalent to the ID field of the
GenBank/EMBL databanks and the id field of the Swissprot/sptrembl
database. In fasta format, the >(\S+) is presumed to be the id,
though some people overload the id to embed other information.
Bioperl does not use any embedded information in the ID field,
and people are encouraged to use other mechanisms (accession
field for example, or extending the sequence object) to solve
this. Notice that $seq->id() maps to this function, mainly for
legacy/convience issues
Returns : A string
Args : None
sub display_id {
my ($obj,$value) = @_;
if( defined $value) {
$obj->{'display_id'} = $value;
return $obj->{'display_id'};
=head2 header()
Title : header()
Usage : $header = $obj->header();
Function: Get/set the header that the user wants printed for this
quality object.
Returns : A string
Args : None
sub header {
my ($obj,$value) = @_;
if( defined $value) {
$obj->{'header'} = $value;
return $obj->{'header'};
=head2 accession_number()
Title : accession_number()
Usage : $unique_biological_key = $obj->accession_number();
Function: Returns the unique biological id for a sequence, commonly
called the accession_number. For sequences from established
databases, the implementors should try to use the correct
accession number. Notice that primary_id() provides the unique id
for the implemetation, allowing multiple objects to have the same
accession number in a particular implementation. For sequences
with no accession number, this method should return "unknown".
Returns : A string
Args : None
sub accession_number {
my( $obj, $acc ) = @_;
if (defined $acc) {
$obj->{'accession_number'} = $acc;
} else {
$acc = $obj->{'accession_number'};
$acc = 'unknown' unless defined $acc;
return $acc;
=head2 primary_id()
Title : primary_id()
Usage : $unique_implementation_key = $obj->primary_id();
Function: Returns the unique id for this object in this implementation.
This allows implementations to manage their own object ids in a
way the implementaiton can control clients can expect one id to
map to one object. For sequences with no accession number, this
method should return a stringified memory location.
Returns : A string
Args : None
sub primary_id {
my ($obj,$value) = @_;
if( defined $value) {
$obj->{'primary_id'} = $value;
return $obj->{'primary_id'};
=head2 desc()
Title : desc()
Usage : $qual->desc($newval);
$description = $qual->desc();
Function: Get/set description text for a qual object
Example :
Returns : Value of desc
Args : newvalue (optional)
sub desc {
my ($obj,$value) = @_;
if( defined $value) {
$obj->{'desc'} = $value;
return $obj->{'desc'};
=head2 id()
Title : id()
Usage : $id = $qual->id();
Function: Return the ID of the quality. This should normally be (and
actually is in the implementation provided here) just a synonym
for display_id().
Returns : A string.
Args : None.
sub id {
my ($self,$value) = @_;
if( defined $value ) {
return $self->display_id($value);
return $self->display_id();
=head2 length()
Title : length()
Usage : $length = $qual->length();
Function: Return the length of the array holding the quality values.
Under most circumstances, this should match the number of quality
values but no validation is done when the PrimaryQual object is
constructed and non-digits could be put into this array. Is this
a bug? Just enough rope...
Returns : A scalar (the number of elements in the quality array).
Args : None.
sub length {
my $self = shift;
if (ref($self->{qual}) ne "ARRAY") {
$self->warn("{qual} is not an array here. Why? It appears to be ".ref($self->{qual})."(".$self->{qual}."). Good thing this can _never_ happen.");
return scalar(@{$self->{qual}});
=head2 qualat()
Title : qualat
Usage : $quality = $obj->qualat(10);
Function: Return the quality value at the given location, where the
first value is 1 and the number is inclusive, ie 1-2 are the first
two bases of the sequence. Start cannot be larger than end but can
be equal.
Returns : A scalar.
Args : A position.
sub qualat {
my ($self,$val) = @_;
my @qualat = @{$self->subqual($val,$val)};
if (scalar(@qualat) == 1) {
return $qualat[0];
} else {
$self->throw("qualat() provided more than one quality.");
=head2 to_string()
Title : to_string()
Usage : $quality = $obj->to_string();
Function: Return a textual representation of what the object contains.
For this module, this function will return:
Returns : A scalar.
Args : None.
sub to_string {
my ($self,$out,$result) = shift;
$out = "qual: ".join(',',@{$self->qual()});
foreach (qw(display_id accession_number primary_id desc id length)) {
$result = $self->$_();
if (!$result) { $result = "<unset>"; }
$out .= "$_: $result\n";
return $out;
sub to_string_automatic {
my ($self,$sub_result,$out) = shift;
foreach (sort keys %$self) {
print("Working on $_\n");
eval { $self->$_(); };
if ($@) { $sub_result = ref($_); }
elsif (!($sub_result = $self->$_())) {
$sub_result = "<unset>";
if (ref($sub_result) eq "ARRAY") {
print("This thing ($_) is an array!\n");
$sub_result = join(',',@$sub_result);
$out .= "$_: ".$sub_result."\n";
return $out;
Jump to Line
Something went wrong with that request. Please try again.