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Bio::Coordinate::Pair - Continuous match between two coordinate sets.


version 1.007001


  use Bio::Location::Simple;
  use Bio::Coordinate::Pair;

  my $match1 = Bio::Location::Simple->new
      (-seq_id => 'propeptide', -start => 21, -end => 40, -strand=>1 );
  my $match2 = Bio::Location::Simple->new
      (-seq_id => 'peptide', -start => 1, -end => 20, -strand=>1 );
  my $pair = Bio::Coordinate::Pair->new(-in => $match1,
                                        -out => $match2
  # location to match
  $pos = Bio::Location::Simple->new
      (-start => 25, -end => 25, -strand=> -1 );

  # results are in a Bio::Coordinate::Result
  # they can be Matches and Gaps; are  Bio::LocationIs
  $res = $pair->map($pos);
  $res->each_match == 1;
  $res->each_gap == 0;
  $res->each_Location == 1;
  $res->match->start == 5;
  $res->match->end == 5;
  $res->match->strand == -1;
  $res->match->seq_id eq 'peptide';


This class represents a one continuous match between two coordinate systems represented by Bio::Location::Simple objects. The relationship is directed and reversible. It implements methods to ensure internal consistency, and map continuous and split locations from one coordinate system to another.

The map() method returns Bio::Coordinate::Results with Bio::Coordinate::Result::Gaps. The calling code have to deal (process or ignore) them.




 Title   : in
 Usage   : $obj->in('peptide');
 Function: Set and read the input coordinate system.
 Example :
 Returns : value of input system
 Args    : new value (optional), Bio::LocationI


 Title   : out
 Usage   : $obj->out('peptide');
 Function: Set and read the output coordinate system.
 Example :
 Returns : value of output system
 Args    : new value (optional), Bio::LocationI


 Title   : swap
 Usage   : $obj->swap;
 Function: Swap the direction of mapping; input <-> output
 Example :
 Returns : 1
 Args    :


 Title   : strand
 Usage   : $obj->strand;
 Function: Get strand value for the pair
 Example :
 Returns : ( 1 | 0 | -1 )
 Args    :


 Title   : test
 Usage   : $obj->test;
 Function: test that both components are of the same length
 Example :
 Returns : ( 1 | undef )
 Args    :


 Title   : map
 Usage   : $newpos = $obj->map($pos);
 Function: Map the location from the input coordinate system
           to a new value in the output coordinate system.
 Example :
 Returns : new Bio::LocationI in the output coordinate system or undef
 Args    : Bio::LocationI object



 Title   : _map
 Usage   : $newpos = $obj->_map($simpleloc);
 Function: Internal method that does the actual mapping. Called
           multiple times by map() if the location to be mapped is a
           split location
 Example :
 Returns : new location in the output coordinate system or undef
 Args    : Bio::Location::Simple


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.                  - General discussion  - About the mailing lists


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.

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 the web:


Heikki Lehvaslaiho <>


This software is copyright (c) by Heikki Lehvaslaiho.

This software is available under the same terms as the perl 5 programming language system itself.