/ 
Algorithm-CriticalPath-0.03
River stage zero No dependents
/ Algorithm::CriticalPath

NAME

Algorithm::CriticalPath - Perform a critical path analysis over a Graph Object, by Ded MedVed

VERSION

Version 0.03

SYNOPSIS

Performs a critical path analysis of a DAG where the vertices have costs, and the edges do not. All costs are assumed positive. Dummy Start and End nodes are used internally to aid the analysis.

The constructor takes a pre-constructed Graph object with weighted vertices and simple directed edges. The Graph object is embedded in the Algorithm::CriticalPath object as a readonly attribute, and cannot be updated once the Algorithm::CriticalPath object has been constructed. The two accessor attributes are 'rw', as I haven't found an easy way to default them from the constructor. They should be 'ro', i.e. not modifiable once set by the constructor.

The module checks that the passed-in Graph object is directed, non-cyclic, and simply connected, without multi-vertices and without multi-edges.

The module has been written on the assumption that no existing CPAN module performs this task.

METHODS

new

  • Algorithm::CriticalPath->new()

    Creates and returns a new Algorithm::CriticalPath object.

    my $g = Graph->new(directed => 1);
$g->add_weighted_vertex('Node1', 1);
$g->add_weighted_vertex('Node2', 2);
$g->add_edge('Node1','Node2');
$g->add_weighted_vertex('Node3', 0.5);
$g->add_edge('Node1','Node3');

my $cp = Algorithm::CriticalPath->new( {graph => $g} );

vertices

  • $g->vertices()

    This returns the critical path as an array of node names.

    my $g = Graph->new(directed => 1);
$g->add_weighted_vertex('Node1', 1);
$g->add_weighted_vertex('Node2', 2);
$g->add_edge('Node1','Node2');
$g->add_weighted_vertex('Node3', 0.5);
$g->add_edge('Node1','Node3');

my $cp = Algorithm::CriticalPath->new( {graph => $g} );
my @orderednodes = $cp->vertices();

cost

  • $g->cost()

    This returns the critical path cost.

    my $g = Graph->new(directed => 1);
$g->add_weighted_vertex('Node1', 1);
$g->add_weighted_vertex('Node2', 2);
$g->add_edge('Node1','Node2');
$g->add_weighted_vertex('Node3', 0.5);
$g->add_edge('Node1','Node3');

my $cp = Algorithm::CriticalPath->new( {graph => $g} );
my $cost = $cp->cost();

AUTHOR

Ded MedVed, <dedmedved at cpan.org>

BUGS

Please report any bugs or feature requests to bug-algorithm-criticalpath at rt.cpan.org, or through the web interface at http://rt.cpan.org/NoAuth/ReportBug.html?Queue=Algorithm-CriticalPath. I will be notified, and then you'll automatically be notified of progress on your bug as I make changes.

SUPPORT

You can find documentation for this module with the perldoc command.

perldoc Algorithm::CriticalPath

You can also look for information at:

ACKNOWLEDGEMENTS

LICENSE AND COPYRIGHT

Copyright 2013 Ded MedVed.

This program is free software; you can redistribute it and/or modify it under the terms of either: the GNU General Public License as published by the Free Software Foundation; or the Artistic License.

See http://dev.perl.org/licenses/ for more information.