File Coverage

blib/lib/Graph/Maker/Beineke.pm

Criterion	Covered	Total	%
statement	9	11	81.8
branch			n/a
condition			n/a
subroutine	4	4	100.0
pod			n/a
total	13	15	86.6

# Copyright 2015, 2016, 2017 Kevin Ryde
#
# This file is part of Graph-Maker-Other.
#
# This file is free software; you can redistribute it and/or modify it
# under the terms of the GNU General Public License as published by the Free
# Software Foundation; either version 3, or (at your option) any later
# version.
#
# This file is distributed in the hope that it will be useful, but
# WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
# or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
# for more details.
#
# You should have received a copy of the GNU General Public License along
# with Graph-Maker-Other.  See the file COPYING.  If not, see
# .

package Graph::Maker::Beineke;
use 5.004;
use strict;
use Carp 'croak';
use Graph::Maker;
use Graph::Maker::Star;
use Graph::Maker::Wheel;

use vars '$VERSION','@ISA';
$VERSION = 8;
@ISA = ('Graph::Maker');


# uncomment this to run the ### lines
# use Smart::Comments;

my @G_data
  = (undef, # 0
     undef, # 1
     [
      # G2    2-----+
      #      / \    |
      #     3---1   5
      #      \ /    |
      #       4-----+
      # https://hog.grinvin.org/ViewGraphInfo.action?id=438
      [1,2],[1,3],[1,4],
      [2,3],[2,5],
      [3,4],
      [4,5],
     ],
     [
      # G3 = K5-e complete 5 less one edge
      #      1
      #     /|\        +----2-----+
      #    / 2 \       |   / \    |
      #   / /|\ \      |  3---1---5
      #  / / 3 \ \     |   \ /    |
      #  |/ / \ \ |    +----4-----+
      #  4--------5
      # https://hog.grinvin.org/ViewGraphInfo.action?id=450
      #
      [1,2],[1,3],[1,4],[1,5],
      [2,3],[2,4],[2,5],
      [3,4], # missing 3,5
      [4,5],
     ],
     [
      # G4      2----6
      #        / \
      #       3---1
      #        \ /
      #         4----5
      # https://hog.grinvin.org/ViewGraphInfo.action?id=922
      #
      [1,2],[1,3],[1,4],
      [2,3],[2,6],
      [3,4],
      [4,5],
     ],
     [
      # G5  +----2----+           2
      #     |   / \   |          /|\
      #     |  3---1  5--6      / 1 \
      #     |   \ /   |        / / \ \
      #     +----4----+        4-----3
      #                        \     /
      #                         \   /
      #                           5----6
      #
      # https://hog.grinvin.org/ViewGraphInfo.action?id=21099
      #
      [1,2],[1,3],[1,4],
      [2,3],[2,4],[2,5],
      [3,4],
      [4,5],
      [5,6],
     ],
     [
      # G6  +----2--\--\              1
      #     |   / \  \  \            /|\
      #     |  3---1  5--6          / 3 \
      #     |   \ /  /  /          / / \ \
      #     +----4--/--/           4-----2
      #                            \ \ / /
      #                             \ 5 /
      #                              \|/
      #                               6
      # https://hog.grinvin.org/ViewGraphInfo.action?id=744
      #
      [1,2],[1,3],[1,4],
      [2,3],[2,5],[2,4],[2,6],
      [3,4],
      [4,5],[4,6],
      [5,6],
     ],
     [
      # G7      2-----6
      #        / \    |
      #       3---1   |
      #        \ /    |
      #         4-----5
      # https://hog.grinvin.org/ViewGraphInfo.action?id=21093
      #
      [1,2],[1,3],[1,4],
      [2,3],[2,6],
      [3,4],
      [4,5],
      [5,6],
     ],
     [
      # G8     2              3---2
      #       / \             | / |
      #      3--1---5         1---4
      #       \ | / |         | / |
      #         4---6         5---6
      # https://hog.grinvin.org/ViewGraphInfo.action?id=21096
      #
      [1,2],[1,3],[1,4],[1,5],
      [2,3],
      [3,4],
      [4,5],[4,6],
      [5,6],
     ],

     # G9 wheel     2----6
     #             / \ / |
     #            3---1  |
     #             \ / \ |
     #              4----5
     # https://hog.grinvin.org/ViewGraphInfo.action?id=204
    );

sub _default_graph_maker {
  require Graph;
  return Graph->new(@_);
}
sub _make_graph {
  my ($params) = @_;
  my $graph_maker = delete($params->{'graph_maker'}) || \&_default_graph_maker;
  return $graph_maker->(%$params);
}

sub init {
  my ($self, %params) = @_;

  my $G = delete($params{'G'}) || 0;
  ### $G

  my $graph;
  if ($G == 1) {
    # G1 = claw = star-4
    # https://hog.grinvin.org/ViewGraphInfo.action?id=204
    #
    $graph = Graph::Maker->new('star', N=>4, %params);

  } elsif ($G == 9) {
    # G9 = wheel 6
    #        2        6 vertices
    #      / | \     10 edges
    #    4---1---3
    #     \ / \  /
    #      5---6
    # https://hog.grinvin.org/ViewGraphInfo.action?id=204
    #
    $graph = Graph::Maker->new('wheel', N=>6, %params);

  } else {
    my $edge_aref = $G_data[$G]
      || croak "Unrecognised G: ", $G;

    $graph = _make_graph(\%params);
    $graph->add_edges(@$edge_aref);
    if ($graph->is_directed) {
      $graph->add_edges(map {[reverse @$_]} @$edge_aref->edges);
    }
  }

  # override possible name from star or wheel
  $graph->set_graph_attribute (name => "Beineke G$G");

  return $graph;
}

Graph::Maker->add_factory_type('Beineke' => __PACKAGE__);
1;

__END__