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# $Id: ace.pm 16969 2010-05-09 15:26:53Z fangly $
#
## BioPerl module for Bio::Assembly::IO::ace
#
# Copyright by Robson F. de Souza (the reading part) and Florent Angly (the
# writing and ACE variants part)
#
# You may distribute this module under the same terms as perl itself
# POD documentation - main docs before the code
=head1 NAME
Bio::Assembly::IO::ace - module to load ACE files from various assembly programs
=head1 SYNOPSIS
# Building an input stream
use Bio::Assembly::IO;
# Load a reference ACE assembly
my $in_io = Bio::Assembly::IO->new( -file => 'results.ace',
-format => 'ace' );
# Read the entire scaffold
my $scaffold = $in_io->next_assembly;
# Or read one contig at a time to save resources
while ( my $contig = $in_io->next_contig ) {
# Do something ...
}
# Assembly writing methods
my $out_io = Bio::Assembly::IO->new( -file => ">output.ace",
-format => 'ace' );
$out_io->write_assembly( -scaffold => $scaffold,
-singlets => 1 );
# Read the '454' Newbler variant of ACE instead of the default 'consed'
# reference ACE variant
my $in_io = Bio::Assembly::IO->new( -file => 'results.ace',
-format => 'ace-454' );
# or ...
my $in_io = Bio::Assembly::IO->new( -file => 'results.ace',
-format => 'ace',
-variant => '454' );
=head1 DESCRIPTION
This package loads the standard ACE files generated by various assembly programs
(Phrap, CAP3, Newbler, Arachne, ...). It was written to be used as a driver
module for Bio::Assembly::IO input/output.
=head2 Implemention
Assemblies are loaded into Bio::Assembly::Scaffold objects composed by
Bio::Assembly::Contig and Bio::Assembly::Singlet objects. Only the ACE file is
used, so if you need singlets, make sure that they are present in the ACE file.
A brief description of the ACE format is available at
http://www.cbcb.umd.edu/research/contig_representation.shtml#ACE
Read the full format description from
http://bozeman.mbt.washington.edu/consed/distributions/README.14.0.txt
In addition to default "_aligned_coord:$seqID" feature class from
Bio::Assembly::Contig, contig objects loaded by this module will have the
following special feature classes in their feature collection:
"_align_clipping:$seqID" (AF)
Location of subsequence in read $seqID which is aligned to the contig. The
coordinates are relative to the contig. If no feature containing this tag is
present the read is considered low quality by Consed.
"_quality_clipping:$seqID" (AF)
The location of high quality subsequence in read $seqID (relative to contig)
"_base_segments" (BS)
Location of read subsequences used to build the consensus
"_read_tags:$readID" (RT)
Sequence features stored as sub_SeqFeatures of the sequence's coordinate
feature (the corresponding "_aligned_coord:$seqID" feature, easily accessed
through get_seq_coord() method).
"_read_desc:$readID" (DS)
Sequence features stored as sub_SeqFeatures of the read's coordinate feature
"consensus tags" (CT)
Equivalent to a bioperl sequence feature and, therefore, are added to the
feature collection using their type field (see Consed's README.txt file) as
primary tag.
"whole assembly tags" (WA)
They have no start and end, as they are not associated to any particular
sequence in the assembly, and are added to the assembly's annotation
collection using "whole assembly" as tag.
=head2 Variants
The default ACE variant is called 'consed' and corresponds to the reference ACE
format.
The ACE files produced by the 454 GS Assembler (Newbler) do not conform to the
reference ACE format. In 454 ACE, the consensus sequence reported covers only
its clear range and the start of the clear range consensus is defined as position
1. Consequently, aligned reads in the contig can have negative positions. Be sure
to use the '454' variant to have positive alignment positions. No attempt is made
to construct the missing part of the consensus sequence (beyond the clear range)
based on the underlying reads in the contig. Instead the ends of the consensus
are simply padded with the gap character '-'.
=head1 FEEDBACK
=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 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
=head2 Support
Please direct usage questions or support issues to the mailing list:
I<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.
=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 web:
https://github.com/bioperl/bioperl-live/issues
=head1 AUTHOR - Robson Francisco de Souza
Email rfsouza@citri.iq.usp.br
=head1 APPENDIX
The rest of the documentation details each of the object
methods. Internal methods are usually preceded with a _
=cut
package Bio::Assembly::IO::ace;
use strict;
use Bio::Assembly::Scaffold;
use Bio::Assembly::Contig;
use Bio::Assembly::Singlet;
use Bio::LocatableSeq;
use Bio::Seq::PrimaryQual;
use Bio::Annotation::SimpleValue;
use Bio::SeqIO;
use Bio::SeqFeature::Generic;
use base qw(Bio::Assembly::IO);
our $line_width = 50;
our $qual_value = 20;
our %variant = ( 'consed' => undef, # default
'454' => undef );
=head1 Parser methods
=head2 next_assembly
Title : next_assembly
Usage : $scaffold = $stream->next_assembly()
Function: returns the next assembly in the stream
Returns : a Bio::Assembly::Scaffold object
Args : none
=cut
sub next_assembly {
my $self = shift;
my $assembly = Bio::Assembly::Scaffold->new();
# Load contigs and singlets in the scaffold
while ( my $obj = $self->next_contig() ) {
# Add contig /singlet to assembly
if ($obj->isa('Bio::Assembly::Singlet')) { # a singlet
$assembly->add_singlet($obj);
} else { # a contig
$assembly->add_contig($obj);
}
}
# Load annotations of assembly and contigs
$self->scaffold_annotations($assembly);
return $assembly;
}
=head2 next_contig
Title : next_contig
Usage : $scaffold = $stream->next_contig()
Function: Returns the next contig or singlet in the ACE stream.
Returns : a Bio::Assembly::Contig or Bio::Assembly::Single object
Args : none
=cut
sub next_contig {
my ($self) = shift;
local $/ = "\n";
my $contigOBJ;
my $read_name;
my $min_start;
my $read_data = {}; # Temporary holder for read data
# Keep reading the ACE stream starting at where we stopped
while ( $_ = $self->_readline) {
chomp;
# Loading contig sequence (COntig sequence field)
if (/^CO\s(\S+)\s(\d+)\s(\d+)\s(\d+)\s(\w+)/xms) { # New contig starts!
if (not $contigOBJ) {
# Start a new contig object
my $contigID = $1; # Contig ID
#my $nof_bases = $2; # Contig length in base pairs
my $nof_reads = $3; # Number of reads in this contig
#my $nof_segments = $4; # Number of read segments selected for consensus assembly
my $ori = $5; # 'C' if contig was complemented or U if not (default)
$ori = $ori eq 'U' ? 1 : -1;
# Create a singlet or contig
if ($nof_reads == 1) { # This is a singlet
$contigOBJ = Bio::Assembly::Singlet->new( );
} elsif ( $nof_reads > 1 ) { # This is a contig
$contigOBJ = Bio::Assembly::Contig->new( );
}
$contigOBJ->id($contigID);
$contigOBJ->strand($ori);
my $consensus_sequence;
while ($_ = $self->_readline) { # Looping over contig lines
chomp; # Drop <ENTER> (\n) on current line
last if (/^$/); # Stop if empty line (contig end) is found
s/\*/-/g; # Forcing '-' as gap symbol
$consensus_sequence .= $_;
}
$consensus_sequence = Bio::LocatableSeq->new(
-seq => $consensus_sequence,
-start => 1,
-strand => $ori,
);
$consensus_sequence->id($contigID);
$contigOBJ->set_consensus_sequence($consensus_sequence);
} else {
# A second contig is about to start. Backtrack one line and go
# to the return statement
$self->_pushback($_);
last;
}
}
# Loading contig qualities... (Base Quality field)
elsif (/^BQ/) {
my $qual_string = '';
while ($_ = $self->_readline) {
chomp;
last if (/^$/);
$qual_string .= "$_ ";
}
my @qual_arr = $self->_input_qual($qual_string, $contigOBJ->get_consensus_sequence->seq);
my $qual = Bio::Seq::PrimaryQual->new(-qual => join(" ", @qual_arr),
-id => $contigOBJ->id() );
$contigOBJ->set_consensus_quality($qual);
}
# Loading read info... (Assembled From field)
elsif (/^AF (\S+) (C|U) (-*\d+)/) {
$read_name = $1; # read ID
my $ori = $2; # strand
my $start = $3; # aligned start
$ori = $ori eq 'U' ? 1 : -1;
$read_data->{$read_name}{'strand'} = $ori;
$read_data->{$read_name}{'padded_start'} = $start;
if ( $self->variant eq '454' ) {
if ( (not defined $min_start) || ($start < $min_start) ) {
$min_start = $start;
}
}
}
# Base segments definitions (Base Segment field)
# They indicate which read segments were used to calculate the consensus
# Coordinates are relative to the contig
elsif (/^BS (\d+) (\d+) (\S+)/) {
my ($start, $end, $contig_id) = ($1, $2, $3);
if ($self->variant eq '454') {
$start += abs($min_start) + 1;
$end += abs($min_start) + 1;
}
my $bs_feat = Bio::SeqFeature::Generic->new(
-start => $start,
-end => $end,
-source => 'ace',
-strand => 1,
-primary => '_base_segments',
-tag => { 'contig_id' => $contig_id}
);
$contigOBJ->add_features([ $bs_feat ], 0);
}
# Loading reads... (ReaD sequence field)
# They define the reads in each contig
elsif (/^RD (\S+) (-*\d+) (\d+) (\d+)/) {
$read_name = $1;
$read_data->{$read_name}{'length'} = $2; # number_of_padded_bases
$read_data->{$read_name}{'contig'} = $contigOBJ;
# $read_data->{$read_name}{'number_of_read_info_items'} = $3;
# $read_data->{$read_name}{'number_of_tags'} = $4;
# Add a read to a contig
my $read_sequence;
while ($_ = $self->_readline) {
chomp;
last if (/^$/);
s/\*/-/g; # Forcing '-' as gap symbol
$read_sequence .= $_; # aligned read sequence
}
my $read = Bio::LocatableSeq->new(
-seq => $read_sequence,
-start => 1,
-strand => $read_data->{$read_name}{'strand'},
-id => $read_name,
-primary_id => $read_name,
-alphabet => 'dna'
);
# Adding read location and sequence to contig ("gapped consensus" coordinates)
my $padded_start = $read_data->{$read_name}{'padded_start'};
if ($self->variant eq '454') {
$padded_start += abs($min_start) + 1;
}
my $padded_end = $padded_start + $read_data->{$read_name}{'length'} - 1;
my $coord = Bio::SeqFeature::Generic->new(
-start => $padded_start,
-end => $padded_end,
-source => 'ace',
-strand => $read_data->{$read_name}{'strand'},
-tag => { 'contig' => $contigOBJ->id }
);
if ($contigOBJ->isa('Bio::Assembly::Singlet')) {
# Set the the sequence in the singlet
$contigOBJ->seqref($read);
} else { # a contig
# this sets the "_aligned_coord:$seqID" feature
$contigOBJ->set_seq_coord($coord,$read);
}
}
# Loading read trimming and alignment ranges...
elsif (/^QA (-?\d+) (-?\d+) (-?\d+) (-?\d+)/) {
my ($qual_start, $qual_end, $aln_start, $aln_end) =
($1, $2, $3, $4);
# Regions of the read that were aligned to the consensus (see BS)
unless ($aln_start == -1 && $aln_end == -1) {
$aln_start = $contigOBJ->change_coord("aligned $read_name",'gapped consensus',$aln_start);
$aln_end = $contigOBJ->change_coord("aligned $read_name",'gapped consensus',$aln_end);
my $aln_feat = Bio::SeqFeature::Generic->new(
-start => $aln_start,
-end => $aln_end,
-strand => $read_data->{$read_name}{'strand'},
-primary => '_align_clipping',
-source => $read_name,
);
$aln_feat->attach_seq( $contigOBJ->get_seq_by_name($read_name) );
$contigOBJ->add_features([ $aln_feat ], 0);
}
# Regions of the read with high quality score
unless ($qual_start == -1 && $qual_end == -1) {
$qual_start = $contigOBJ->change_coord("aligned $read_name",'gapped consensus',$qual_start);
$qual_end = $contigOBJ->change_coord("aligned $read_name",'gapped consensus',$qual_end);
my $qual_feat = Bio::SeqFeature::Generic->new(
-start => $qual_start,
-end => $qual_end,
-strand => $read_data->{$read_name}{'strand'},
-primary => '_quality_clipping',
-source => $read_name || '',
);
$qual_feat->attach_seq( $contigOBJ->get_seq_by_name($read_name) );
$contigOBJ->add_features([ $qual_feat ], 0);
}
}
# Loading read DeScription (DS)
elsif (/^DS\s+(.*)/) {
my $desc = $1;
# Expected tags are CHROMAT_FILE, PHD_FILE, TIME and to a lesser
# extent DYE, TEMPLATE, CHEM and DIRECTION, but any other tag is
# allowed
my (undef, %tags) = split /\s?(\S+):\s+/, $desc;
my $coord = $contigOBJ->get_seq_coord( $contigOBJ->get_seq_by_name($read_name) );
my $start = $coord->start;
my $end = $coord->end;
my $read_desc = Bio::SeqFeature::Generic->new(
-start => $start,
-end => $end,
-primary => '_read_desc', # primary_tag
-source => $read_name || '',
-tag => \%tags
);
$contigOBJ->get_features_collection->add_features([$read_desc]);
$contigOBJ->get_features_collection->add_SeqFeature($coord, $read_desc);
}
# Loading Read Tags
elsif (/^RT\s*\{/) {
my ($readID,$type,$source,$start,$end,$date) = split(' ',$self->_readline);
my $extra_info = undef;
while ($_ = $self->_readline) {
last if (/\}/);
$extra_info .= $_;
}
$start = $contigOBJ->change_coord("aligned $readID",'gapped consensus',$start);
$end = $contigOBJ->change_coord("aligned $readID",'gapped consensus',$end);
my $read_tag = Bio::SeqFeature::Generic->new(
-start => $start,
-end => $end,
-primary => '_read_tags',
-source => $readID || '',
-tag => { 'type' => $type,
'source' => $source,
'creation_date' => $date}
);
$read_tag->add_tag_value('extra_info', $extra_info) if defined $extra_info;
my $contig = $read_data->{$readID}{'contig'};
my $coord = $contig->get_seq_coord( $contig->get_seq_by_name($readID) );
$contig->get_features_collection->add_features([$read_tag]);
$contig->get_features_collection->add_SeqFeature($coord, $read_tag);
}
}
# Adjust consensus sequence of 454 variant by padding its start and end
if (($self->variant eq '454') && (defined $contigOBJ)) {
my $pad_char = '-';
my $pad_score = 0;
# Find maximum coordinate
my $max_end;
for my $readid ($contigOBJ->get_seq_ids) {
my ($alncoord) = $contigOBJ->get_features_collection->get_features_by_type("_aligned_coord:$readid");
my $end = $alncoord->location->end;
if ( (not defined $max_end) || ($end > $max_end) ) {
$max_end = $end;
}
}
# Pad consensus sequence
my $cons_seq = $contigOBJ->get_consensus_sequence;
my $cons_string = $cons_seq->seq;
my $l_pad_len = abs($min_start) + 1;
my $r_pad_len = $max_end - length($cons_string) - $l_pad_len;
$cons_string = $pad_char x $l_pad_len . $cons_string . $pad_char x $r_pad_len;
$cons_seq = Bio::LocatableSeq->new(
-seq => $cons_string,
-id => $cons_seq->id,
-start => $cons_seq->start,
-strand => $cons_seq->strand,
);
$contigOBJ->set_consensus_sequence($cons_seq);
# Pad consensus quality
my $cons_qual = $contigOBJ->get_consensus_quality;
if (defined $cons_qual) {
my $cons_score = [ ($pad_score) x $l_pad_len,
@{$cons_qual->qual},
($pad_score) x $r_pad_len ];
$cons_qual = Bio::Seq::PrimaryQual->new(
-qual => join(' ', @$cons_score),
-id => $cons_qual->id
);
$contigOBJ->set_consensus_quality($cons_qual);
}
}
return $contigOBJ;
}
=head2 scaffold_annotations
Title : scaffold_annotations
Usage : $stream->scaffold_annotations($scaffold)
Function: Add assembly and contig annotations to a scaffold. In the ACE format,
annotations are the WA and CT tags.
Returns : 1 for success
Args : a Bio::Assembly::Scaffold object to attach the annotations to
=cut
sub scaffold_annotations {
my ($self, $assembly) = @_;
local $/ = "\n";;
# Read the ACE stream from the beginning again
seek($self->_fh, 0, 0);
while ($_ = $self->_readline) {
chomp;
# Assembly information (ASsembly field)
# Ignore it
#(/^AS\s+(\d+)\s+(\d+)/) && do {
# my $nof_contigs = $1;
# my $nof_seq_in_contigs = $2;
#};
# Loading Whole Assembly tags
/^WA\s*\{/ && do {
my ($type,$source,$date) = split(' ',$self->_readline);
my $extra_info = undef;
while ($_ = $self->_readline) {
last if (/\}/);
$extra_info .= $_;
}
my $assembly_tags = join(" ","TYPE:",$type,"PROGRAM:",$source,
"DATE:",$date,"DATA:",$extra_info);
$assembly_tags = Bio::Annotation::SimpleValue->new(-value=>$assembly_tags);
$assembly->annotation->add_Annotation('whole assembly',$assembly_tags);
};
# Loading Contig Tags (a.k.a. Bioperl features)
/^CT\s*\{/ && do {
my ($contigID,$type,$source,$start,$end,$date) = split(' ',$self->_readline);
my %tags = ('source' => $source, 'creation_date' => $date);
my $tag_type = 'extra_info';
while ($_ = $self->_readline) {
if (/COMMENT\s*\{/) {
$tag_type = 'comment';
} elsif (/C\}/) {
$tag_type = 'extra_info';
} elsif (/\}/) {
last;
} else {
$tags{$tag_type} .= "$_";
}
}
my $contig_tag = Bio::SeqFeature::Generic->new( -start => $start,
-end => $end,
-primary => $type,
-source => 'ace',
-tag => \%tags );
my $contig = $assembly->get_contig_by_id($contigID) ||
$assembly->get_singlet_by_id($contigID);
$self->throw("Cannot add feature to unknown contig '$contigID'")
unless defined $contig;
$contig->add_features([ $contig_tag ],1);
};
}
return 1;
}
=head2 write_assembly
Title : write_assembly
Usage : $ass_io->write_assembly($assembly)
Function: Write the assembly object in ACE compatible format. The contig IDs
are sorted naturally if the Sort::Naturally module is present, or
lexically otherwise. Internally, write_assembly use the
write_contig, write_footer and write_header methods. Use these
methods if you want more control on the writing process.
Returns : 1 on success, 0 for error
Args : A Bio::Assembly::Scaffold object
=cut
=head2 write_contig
Title : write_contig
Usage : $ass_io->write_contig($contig)
Function: Write a contig or singlet object in ACE compatible format. Quality
scores are automatically generated if the contig does not contain
any
Returns : 1 on success, 0 for error
Args : A Bio::Assembly::Contig or Singlet object
=cut
sub write_contig {
my ($self, @args) = @_;
my ($contig) = $self->_rearrange([qw(CONTIG)], @args);
# Sanity check
if ( !$contig || !$contig->isa('Bio::Assembly::Contig') ) {
$self->throw("Must provide a Bio::Assembly::Contig or Singlet object when calling write_contig");
}
# Contig consensus sequence
my $contig_id = $contig->id;
my $cons = $contig->get_consensus_sequence;
my $cons_seq = $cons->seq;
my $cons_len = $cons->length;
my $contig_num_reads = $contig->num_sequences;
my $cons_strand = ($contig->strand == -1) ? 'C' : 'U';
my @bs_feats = $contig->get_features_collection->get_features_by_type('_base_segments');
my $nof_segments = scalar @bs_feats;
$self->_print(
"CO $contig_id $cons_len $contig_num_reads $nof_segments $cons_strand\n".
_formatted_seq($cons_seq, $line_width).
"\n"
);
# Consensus quality scores
$cons = $contig->get_consensus_quality;
my $cons_qual = $cons->qual if defined $cons;
$self->_print(
"BQ\n".
_formatted_qual($cons_qual, $cons_seq, $line_width, $qual_value).
"\n"
);
# Read entries
my @reads = $contig->each_seq;
for my $read (@reads) {
my $read_id = $read->id;
my $read_strand = ($read->strand == -1) ? 'C' : 'U';
my $read_start = $contig->change_coord("aligned $read_id",'gapped consensus',1);
$self->_print( "AF $read_id $read_strand $read_start\n" );
}
$self->_print( "\n" );
# Deal with base segments (BS)
if ( @bs_feats ) {
# sort segments by increasing start position
@bs_feats = sort { $a->start <=> $b->start } @bs_feats;
# write segments
for my $bs_feat ( @bs_feats ) {
my $start = $bs_feat->start;
my $end = $bs_feat->end;
my $id = ($bs_feat->get_tag_values('contig_id'))[0];
$self->_print( "BS $start $end $id\n" );
}
$self->_print( "\n" );
}
for my $read (@reads) {
$self->_write_read($read, $contig);
}
return 1;
}
=head2 write_header
Title : write_header
Usage : $ass_io->write_header($scaffold)
or
$ass_io->write_header(\@contigs);
or
$ass_io->write_header();
Function: Write ACE header (AS tags). You can call this function at any time,
i.e. not necessarily at the start of the stream - this is useful
if you have an undetermined number of contigs to write to ACE, e.g:
for my $contig (@list_of_contigs) {
$ass_io->_write_contig($contig);
}
$ass_io->_write_header();
Returns : 1 on success, 0 for error
Args : A Bio::Assembly::Scaffold
or
an arrayref of Bio::Assembly::Contig
or
nothing (the header is dynamically written based on the ACE file
content)
=cut
sub write_header {
my ($self, $input) = @_;
# Input validation
my @contigs;
my $err_msg = "If an input is given to write_header, it must be a single ".
"Bio::Assembly::Scaffold object or an arrayref of Bio::Assembly::Contig".
" or Singlet objects";
my $ref = ref $input;
if ( $ref eq 'ARRAY' ) {
for my $obj ( @$input ) {
$self->throw($err_msg) if not $obj->isa('Bio::Assembly::Contig');
push @contigs, $obj;
}
} elsif ( $ref =~ m/Bio::Assembly::Scaffold/ ) {
@contigs = ($input->all_contigs, $input->all_singlets);
}
# Count number of contigs and reads
my $num_contigs = 0;
my $num_reads = 0;
if ( scalar @contigs > 0 ) {
# the contigs were provided
$num_contigs = scalar @contigs;
for my $contig ( @contigs ) {
$num_reads += $contig->num_sequences;
}
} else {
# need to read the contigs from file
$self->flush;
my $file = $self->file(); # e.g. '+>output.ace'
$file =~ s/^\+?[><]?//; # e.g. 'output.ace'
my $read_io = Bio::Assembly::IO->new( -file => $file, -format => 'ace' );
while ( my $contig = $read_io->next_contig ) {
$num_contigs++;
$num_reads += $contig->num_sequences;
}
$read_io->close;
}
# Write ASsembly tag at the start of the file
my $header = "AS $num_contigs $num_reads\n\n";
$self->_insert($header, 1);
return 1;
}
=head2 write_footer
Title : write_footer
Usage : $ass_io->write_footer($scaffold)
Function: Write ACE footer (WA and CT tags).
Returns : 1 on success, 0 for error
Args : A Bio::Assembly::Scaffold object (optional)
=cut
sub write_footer {
my ($self, $scaf) = @_;
# Nothing to write if scaffold was not provided
return 1 if not defined $scaf;
# Verify that provided object is a scaffold
if ($scaf->isa('Bio::Assembly:ScaffoldI')) {
$self->throw("Must provide a Bio::Assembly::Scaffold object when calling write_footer");
}
# Whole Assembly tags (WA)
my $asm_anno = ($scaf->annotation->get_Annotations('whole assembly'))[0];
if ($asm_anno) {
my $asm_tags = $asm_anno->value;
if ($asm_tags =~ m/^TYPE: (\S+) PROGRAM: (\S+) DATE: (\S+) DATA: (.*)$/ms) {
my ($type, $program, $date, $data) = ($1, $2, $3, $4);
$data ||= '';
$self->_print(
"WA{\n".
"$type $program $date\n".
$data.
"}\n".
"\n"
);
}
}
# Contig Tags (CT)
for my $contig_id ( Bio::Assembly::IO::_sort( $scaf->get_contig_ids ) ) {
my $contig = $scaf->get_contig_by_id($contig_id) ||
$scaf->get_singlet_by_id($contig_id);
# Is there a better way of doing this? Grepping is not very efficient...
my @feats = (grep
{ not $_->primary_tag =~ m/^_/ }
$contig->get_features_collection->features
);
for my $feat (@feats) {
my $type = $feat->primary_tag;
my $start = $feat->start;
my $end = $feat->end;
my $source = ($feat->get_tag_values('source') )[0];
my $date = ($feat->get_tag_values('creation_date'))[0];
my $extra = '';
if ($feat->has_tag('extra_info')) {
$extra = ($feat->get_tag_values('extra_info') )[0];
}
$self->_print(
"CT{\n".
"$contig_id $type $source $start $end $date\n".
$extra.
"}\n".
"\n"
);
}
}
return 1;
}
=head2 variant
Title : variant
Usage : $variant = $ass_io->variant();
Function: Get and set method for the assembly variant. This is important since
not all assemblers respect the reference ACE format.
Returns : string
Args : string: 'consed' (default) or '454'
=cut
# variant() method inherited from Bio::Root::IO
=head2 _write_read
Title : _write_read
Usage : $ass_io->_write_read($read, $contig)
Function: Write a read object in ACE compatible format
Returns : 1 on success, 0 for error
Args : a Bio::LocatableSeq read
the Contig or Singlet object that this read belongs to
=cut
sub _write_read {
my ($self, @args) = @_;
my ($read, $contig) = $self->_rearrange([qw(READ CONTIG)], @args);
# Sanity check
if ( !$read || !$read->isa('Bio::LocatableSeq') ) {
$self->throw("Must provide a Bio::LocatableSeq when calling write_read");
}
if ( !$contig || !$contig->isa('Bio::Assembly::Contig') ) {
$self->throw("Must provide a Bio::Assembly::Contig or Singlet object when calling write_read");
}
# Read info
my $read_id = $read->id;
my $read_len = $read->length; # aligned length
my $read_seq = $read->seq;
my $nof_info = 0; # fea: could not find exactly the meaning of this?
my @read_tags = $contig->get_features_collection->get_SeqFeatures(
$contig->get_seq_coord($read), "_read_tags:$read_id");
my $nof_tags = scalar @read_tags;
$self->_print(
"RD $read_id $read_len $nof_info $nof_tags\n".
_formatted_seq($read_seq, $line_width).
"\n"
);
# Aligned "align clipping" and quality coordinates if read object has them
my $qual_clip_start = 1;
my $qual_clip_end = length($read->seq);
my ($qual_clip) = $contig->get_features_collection->get_features_by_type("_quality_clipping:$read_id");
if ( defined $qual_clip ) {
$qual_clip_start = $qual_clip->location->start;
$qual_clip_end = $qual_clip->location->end;
$qual_clip_start = $contig->change_coord('gapped consensus',"aligned $read_id",$qual_clip_start);
$qual_clip_end = $contig->change_coord('gapped consensus',"aligned $read_id",$qual_clip_end );
}
my $aln_clip_start = 1;
my $aln_clip_end = length($read->seq);
my ($aln_clip) = $contig->get_features_collection->get_features_by_type("_align_clipping:$read_id");
if ( defined $aln_clip ) {
$aln_clip_start = $aln_clip->location->start;
$aln_clip_end = $aln_clip->location->end;
$aln_clip_start = $contig->change_coord('gapped consensus',"aligned $read_id",$aln_clip_start );
$aln_clip_end = $contig->change_coord('gapped consensus',"aligned $read_id",$aln_clip_end );
}
$self->_print(
"QA $qual_clip_start $qual_clip_end $aln_clip_start $aln_clip_end\n".
"\n"
);
# Read description, if read object has them
my $read_desc = ( $contig->get_features_collection->get_SeqFeatures(
$contig->get_seq_coord($read), "_read_desc:$read_id") )[0];
if ($read_desc) {
$self->_print("DS");
for my $tag_name ( $read_desc->get_all_tags ) {
my $tag_value = ($read_desc->get_tag_values($tag_name))[0];
$self->_print(" $tag_name: $tag_value");
}
$self->_print("\n\n");
}
# Read tags, if read object has them
for my $read_tag (@read_tags) {
#my $type = $read_tag->primary_tag;
my $start = $read_tag->start;
my $end = $read_tag->end;
my $type = ($read_tag->get_tag_values('type') )[0];
my $source = ($read_tag->get_tag_values('source') )[0];
my $date = ($read_tag->get_tag_values('creation_date'))[0];
my $extra = $read_tag->has_tag('extra_info') ?
($read_tag->get_tag_values('extra_info') )[0] : '';
$self->_print(
"RT{\n".
"$read_id $type $source $start $end $date\n".
$extra.
"}\n".
"\n"
);
}
return 1;
}
=head2 _formatted_seq
Title : _formatted_seq
Usage : Bio::Assembly::IO::ace::_formatted_seq($sequence, $line_width)
Function: Format a sequence for ACE output:
i ) replace gaps in the sequence by the '*' char
ii) split the sequence on multiple lines as needed
Returns : new sequence string
Args : sequence string on one line
maximum line width
=cut
sub _formatted_seq {
my ($seq_str, $line_width) = @_;
my $new_str = '';
# In the ACE format, gaps are '*'
$seq_str =~ s/-/*/g;
# Split sequences on several lines
while ( my $chunk = substr $seq_str, 0, $line_width, '' ) {
$new_str .= "$chunk\n";
}
return $new_str;
}
=head2 _formatted_qual
Title : _formatted_qual
Usage : Bio::Assembly::IO::ace::_formatted_qual($qual_arr, $sequence, $line_width, $qual_default)
Function: Format quality scores for ACE output:
i ) use the default quality values when they are missing
ii ) remove gaps (they get no score in ACE)
iii) split the quality scores on several lines as needed
Returns : new quality score string
Args : quality score array reference
corresponding sequence string
maximum line width
default quality score
=cut
sub _formatted_qual {
my ($qual_arr, $seq, $line_width, $qual_default) = @_;
my $qual_str = '';
my @qual_arr;
if (defined $qual_arr) {
# Copy array
@qual_arr = @$qual_arr;
} else {
# Default quality
@qual_arr = map( $qual_default, (1 .. length $seq) );
}
# Gaps get no quality score in ACE format
my $gap_pos = -1;
while ( 1 ) {
$gap_pos = index($seq, '-', $gap_pos + 1);
last if $gap_pos == -1;
substr $seq, $gap_pos, 1, '';
splice @qual_arr, $gap_pos, 1;
$gap_pos--;
}
# Split quality scores on several lines
while ( my @chunks = splice @qual_arr, 0, $line_width ) {
$qual_str .= "@chunks\n";
}
return $qual_str;
}
=head2 _input_qual
Title : _input_qual
Usage : Bio::Assembly::IO::ace::_input_qual($qual_string, $sequence)
Function: Reads input quality string and converts it to an array of quality
scores. Gaps get a quality score equals to the average of the
quality score of its neighbours.
Returns : new quality score array
Args : quality score string
corresponding sequence string
=cut
sub _input_qual {
my ($self, $qual_string, $sequence) = @_;
my @qual_arr = ();
# Remove whitespaces in front of qual string and split quality values
$qual_string =~ s/^\s+//;
my @tmp = split(/\s+/, $qual_string);
# Remove gaps
my $i = 0; # position in quality
my $j = 0; # position in sequence
my $prev = 0;
my $next = 0;
for $j (0 .. length($sequence)-1) {
my $nt = substr($sequence, $j, 1);
if ($nt eq '-') {
if ($i > 0) {
$prev = $tmp[$i-1];
} else {
$prev = 0;
}
if ($i < $#tmp) {
$next = $tmp[$i];
} else {
$next = 0;
}
push @qual_arr, int(($prev+$next)/2);
} else {
push @qual_arr, $tmp[$i];
$i++;
}
}
return @qual_arr;
}
=head2 _initialize
Title : _initialize
Usage : $ass_io->_initialize(@args)
Function: Initialize the Bio::Assembly::IO object with the proper ACE variant
Returns :
Args :
=cut
sub _initialize {
my($self, @args) = @_;
$self->SUPER::_initialize(@args);
my ($variant) = $self->_rearrange([qw(VARIANT)], @args);
$variant ||= 'consed';
$self->variant($variant);
}
1;
__END__
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