Provided by: libbio-perl-perl_1.6.901-2_all bug

NAME

       Bio::Tools::Phylo::PAML::Codeml - Parses output from the PAML program codeml.

SYNOPSIS

         #!/usr/bin/perl -Tw
         use strict;

         use Bio::Tools::Phylo::PAML::Codeml;

         # need to specify the output file name (or a fh) (defaults to
         # -file => "codeml.mlc"); also, optionally, the directory in which
         # the other result files (rst, 2ML.dS, etc) may be found (defaults
         # to "./")
         my $parser = new Bio::Tools::Phylo::PAML::Codeml::Parser
           (-file => "./results/mlc", -dir => "./results/");

         # get the first/next result; a Bio::[...]::Codeml::Result object
         my $result = $parser->next_result();

         # get the sequences used in the analysis; returns Bio::PrimarySeq
         # objects (OTU = Operational Taxonomic Unit).
         my @otus = $result->get_seqs();

         # codon summary: codon usage of each sequence [ arrayref of {
         # hashref of counts for each codon } for each sequence and the
         # overall sum ], and positional nucleotide distribution [ arrayref
         # of { hashref of frequencies for each nucleotide } for each
         # sequence and overall frequencies ].

         my ($codonusage, $ntdist) = $result->get_codon_summary();

         # example manipulations of $codonusage and $ntdist:
         printf "There were %d '%s' codons in the first seq (%s)\n",
           $codonusage->[0]->{AAA}, 'AAA', $otus[0]->id();
         printf "There were %d '%s' codons used in all the sequences\n",
           $codonusage->[$#{$codonusage}]->{AAA}, 'AAA';
         printf "Nucleotide '%c' was present %g of the time in seq %s\n",
           'A', $ntdist->[1]->{A}, $otus[1]->id();

         # get Nei & Gojobori dN/dS matrix:
         my $NGmatrix = $result->get_NGmatrix();

         # get ML-estimated dN/dS matrix, if calculated; this corresponds to
         # the runmode = -2, pairwise comparison usage of codeml
         my $MLmatrix = $result->get_MLmatrix();

         # These matrices are length(@otu) x length(@otu) "strict lower
         # triangle" 2D-matrices, which means that the diagonal and
         # everything above it is undefined.  Each of the defined cells is a
         # hashref of estimates for "dN", "dS", "omega" (dN/dS ratio), "t",
         # "S" and "N".  If a ML matrix, "lnL" will also be defined.  Any
         # additional ML parameters estimated by the model will be in an
         # array ref under "params"; it's up to the user to know which
         # position corresponds to which parameter (since PAML doesn't label
         # them, and we can't guess very well yet (a TODO I guess).

         printf "The omega ratio for sequences %s vs %s was: %g\n",
           $otus[0]->id, $otus[1]->id, $MLmatrix->[0]->[1]->{omega};

         # with a little work, these matrices could also be passed to
         # Bio::Tools::Run::Phylip::Neighbor, or other similar tree-building
         # method that accepts a matrix of "distances" (using the LOWTRI
         # option):
         my $distmat = [ map { [ map { $$_{omega} } @$_ ] } @$MLmatrix ];

         # for runmode's other than -2, get tree topology with estimated
         # branch lengths; returns a Bio::Tree::TreeI-based tree object with
         # added PAML parameters at each node
         my $tree = $result->get_tree();
         for my $node ($tree->get_nodes()) {
            # inspect the tree: the "t" (time) parameter is available via
            # $node->branch_length(); all other branch-specific parameters
            # ("omega", "dN", etc.) are available via $node->param('omega');
         }

         # get any general model parameters: kappa (the
         # transition/transversion ratio), NSsites model parameters ("p0",
         # "p1", "w0", "w1", etc.), etc.
         my $params = $result->get_model_params();
         printf "M1 params: p0 = %g\tp1 = %g\n", $params->{p0}, $params->{p1};

         # for NSsites models, obtain posterior probabilities for membership
         # in each class for every position; probabilities correspond to
         # classes w0, w1, ... etc.
         my @probs = $result->get_posteriors();

         # find, say, positively selected sites!
         if ($params->{w2} > 1) {
           for (my $i = 0; $i < @probs ; $i++) {
             if ($probs[$i]->[2] > 0.5) {
                # assumes model M1: three w's, w0, w1 and w2 (positive selection)
                printf "position %d: (%g prob, %g omega, %g mean w)\n",
                  $i, $probs[$i]->[2], $params->{w2}, $probs[$i]->[3];
             }
           }
         } else { print "No positive selection found!\n"; }

DESCRIPTION

       This module is used to parse the output from the PAML program codeml.  You can use the
       Bio::Tools::Run::Phylo::Phylo::PAML::Codeml module to actually run codeml; this module is
       only useful to parse the output.

FEEDBACK

   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 list.  Your participation
       is much appreciated.

         bioperl-l@bioperl.org              - General discussion
         http://bioperl.org/MailList.shtml  - About the mailing lists

   Reporting Bugs
       Report bugs to the Bioperl bug tracking system to help us keep track of the bugs and their
       resolution. Bug reports can be submitted via email or the web:

         bioperl-bugs@bioperl.org
         http://bioperl.org/bioperl-bugs/

AUTHOR - Jason Stajich, Aaron Mackey

       Email jason@bioperl.org Email amackey@virginia.edu

TODO

       This module should also be able to handle "codemlsites" batch output...

APPENDIX

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

   new
        Title   : new
        Usage   : my $obj = new Bio::Tools::Phylo::PAML::Codeml();
        Function: Builds a new Bio::Tools::Phylo::PAML::Codeml object
        Returns : Bio::Tools::Phylo::PAML::Codeml
        Args    :

   get_trees
        Title   : get_trees
        Usage   : my @trees = $codemlparser->get_trees();
        Function: Returns a list of trees (if any) are in the output file
        Returns : List of L<Bio::Tree::TreeI> objects
        Args    : none

   get_statistics
        Title   : get_statistics
        Usage   : my $data = $codemlparser->get_statistics
        Function: Retrieves the set of pairwise comparisons
        Returns : Hash Reference keyed as 'seqname' -> 'seqname' -> 'datatype'
        Args    : none