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::Quality where these quality values are associated with the sequence information.


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AUTHOR - Chad Matsalla



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


 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


 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.


 Title    : seq()
 Usager   : $sequence = $obj->seq();
 Function : Returns the quality numbers as a space-separated string.
 Returns  : Single string.
 Args     : None.


 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


 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


 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


 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


 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 implementation, 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


 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 implementation 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


 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)


 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.


 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.


 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.


 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.