Summary

Bio::AlignIO::largemultifasta - Largemultifasta MSA Sequence
input/output stream

Package variables

Included modules

Inherit

Bio::AlignIO Bio::SeqIO Bio::SimpleAlign

Synopsis

Do not use this module directly. Use it via the Bio::AlignIO class.

Description

This object can transform Bio::SimpleAlign objects to and from
largemultifasta flat file databases. This is for the fasta sequence
format NOT FastA analysis program. To process the pairwise alignments
from a FastA (FastX, FastN, FastP, tFastA, etc) use the Bio::SearchIO
module.
Reimplementation of Bio::AlignIO::fasta modules so that creates
temporary files instead of keeping the whole sequences in memory.

Methods

Methods description

 Title   : next_seq
 Usage   : $seq = $stream->next_seq()
 Function: returns the next sequence in the stream while taking care
           of the length
 Returns : Bio::Seq object
 Args    : NONE

 Title   : next_aln
 Usage   : $aln = $stream->next_aln()
 Function: returns the next alignment in the stream.
 Returns : Bio::Align::AlignI object - returns 0 on end of file
	    or on error
 Args    : NONE

 Title   : write_aln
 Usage   : $stream->write_aln(@aln)
 Function: writes the $aln object into the stream in largemultifasta format
 Returns : 1 for success and 0 for error
 Args    : Bio::Align::AlignI object

Methods code

sub _initialize {

  my($self,@args) = @_;
  $self->SUPER::_initialize(@args);
  if( ! defined $self->sequence_factory ) {
      $self->sequence_factory(new Bio::Seq::SeqFactory
			      (-verbose => $self->verbose(),
			       -type => 'Bio::Seq::LargeLocatableSeq'));
  }

}

sub next_seq {

    my ($self) = @_;
    my $largeseq = $self->sequence_factory->create();
    my ($id,$fulldesc,$entry);
    my $count = 0;
    my $seen = 0;
    while( defined ($entry = $self->_readline) ) {
	if( $seen == 1 && $entry =~ /^\s*>/ ) {
	    $self->_pushback($entry);
	    return $largeseq;
	}
	if ( ($entry eq '>')  ) { $seen = 1; next; }
	elsif( $entry =~ /\s*>(.+?)$/ ) {
	    $seen = 1;
	    ($id,$fulldesc) = ($1 =~ /^\s*(\S+)\s*(.*)$/)
		or $self->warn("Can't parse fasta header");
	    $largeseq->display_id($id);
	    $largeseq->primary_id($id);
	    $largeseq->desc($fulldesc);
	} else {
	    $entry =~ s/\s+//g;
	    $largeseq->add_sequence_as_string($entry);
	}
	(++$count % 1000 == 0 && $self->verbose() > 0) && print "line $count\n";
    }
    if( ! $seen ) { return; }
    return $largeseq;

}

sub next_aln {

    my $self = shift;
    my $largeseq;
    my $aln =  Bio::SimpleAlign->new();
    while (defined ($largeseq = $self->next_seq) ) {
        $aln->add_seq($largeseq);
        $self->debug("sequence readed\n");
    }

    my $alnlen = $aln->length;
    foreach my $largeseq ( $aln->each_seq ) {
	if( $largeseq->length < $alnlen ) {
	    my ($diff) = ($alnlen - $largeseq->length);
	    $largeseq->seq("-" x $diff);
	}
    }

    return $aln;

}

sub write_aln {

    my ($self,@aln) = @_;
    my ($seq,$desc,$rseq,$name,$count,$length,$seqsub);

    foreach my $aln (@aln) {
	if( ! $aln || ! $aln->isa('Bio::Align::AlignI')  ) {
	    $self->warn("Must provide a Bio::Align::AlignI object when calling write_aln");
	    next;
	}
	foreach $rseq ( $aln->each_seq() ) {
	    $name = $aln->displayname($rseq->get_nse());
	    $seq  = $rseq->seq();
	    $desc = $rseq->description || '';
	    $self->_print (">$name $desc\n") or return ;
	    $count =0;
	    $length = length($seq);
	    while( ($count * 60 ) < $length ) {
		$seqsub = substr($seq,$count*60,60);
		$self->_print ("$seqsub\n") or return ;
		$count++;
	    }
	}
    }
    $self->flush if $self->_flush_on_write && defined $self->_fh;
    return 1;

}

General documentation

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:

  http://bugzilla.open-bio.org/

Email: avilella-at-gmail-dot-com, heikki-at-bioperl-dot-org

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