���� JFIF



�� �         "" $(4,$&1'-=-157:::#+?D?8C49:7
 7%%77777777777777777777777777777777777777777777777777��  { �
" 

�� 



 �� 5
 
!1AQa"q�2��BR��#b������� 



�� 
�� 
 ? ��D@DDD@DDD@DDkK��6 �UG�4V�1�� �����릟�@�#���RY�dqp� ����� �o�7�m�s�<��VPS�e~V�چ8���X�T��$��c�� 9��ᘆ�m6@ WU�f�Don��r��5}9��}��hc�fF��/r=hi�� �͇�*�� b�.��$0�&te��y�@�A�F�=� P




f�A��a���˪�Œ�É��U|� � 3\�״ H SZ�g46�C��צ�ے �b<���;m����Rpع^��l7��*�����TF�}�\�M���M%�'�����٠ݽ�v� ��!-�����?�N!La��A+[`#���M����'�~oR�?��v^)��=��h����A��X�.���˃����^Ə��ܯsO"B�c>; �e�4��5�k��/CB��.  �J?��;�҈�������������������~�<�VZ�ꭼ2/)Í”jC���ע�V�G�!���!�F������\�� Kj�R�oc�h���:Þ I��1"2�q×°8��Р@ז���_C0�ր
��A��lQ��@纼�!7��F�� �]�sZ B�62r�v�z~�K�7�c��5�.���ӄq&�Z�d�<�kk���T&8�|���I���� Ws}���ǽ�cqnΑ�_���3��|N�-y,��i���ȗ_�\60��
�@��6����D@DDD@DDD@DDD@DDD@DDc�KN66<�c��64=r����� Ď0��h���t&(�hnb[� ?��^��\��â|�,�
/h�\��R��5�? �0�!צ܉-����G����٬��Q�zA���1�����V��� �:R���`�$��ik��H����D4�����#dk����� h�}����7���w%�������*o8wG�Lycu
T�.���ܯ7��I��u^���)��/c�,s�Nq�ۺ�;�ך�YH2���.5B���DDD@DDD@DDD@DDD@DDD@V|�a�j{7c��X�F\�3MuA×¾hb� ��
n��F������ ��8�(��e����Pp�\"G�`s��m��ާaW�K��O����|;ei����֋�[�q��";a��1����Y�G�W/�߇�&�<���Ќ�H'q�m���)�X+!���=�m�ۚ丷~6a^X�)���,�>#&6G���Y��{����"" """ """ """ """ ""��at\/�a�8 �yp%�lhl�n����)��
�i�t��B�������������?�� | // +-----------------------------------------------------------------------------+ // /** * This file contains the definition of the Structures_Graph_Node class * * @see Structures_Graph_Node * @package Structures_Graph */ /* dependencies {{{ */ /** */ require_once 'PEAR.php'; /** */ require_once 'Structures/Graph.php'; /* }}} */ /* class Structures_Graph_Node {{{ */ /** * The Structures_Graph_Node class represents a Node that can be member of a * graph node set. * * A graph node can contain data. Under this API, the node contains default data, * and key index data. It behaves, thus, both as a regular data node, and as a * dictionary (or associative array) node. * * Regular data is accessed via getData and setData. Key indexed data is accessed * via getMetadata and setMetadata. * * @author S�rgio Carvalho * @copyright (c) 2004 by S�rgio Carvalho * @package Structures_Graph */ /* }}} */ class Structures_Graph_Node { /* fields {{{ */ /** * @access private */ var $_data = null; /** @access private */ var $_metadata = array(); /** @access private */ var $_arcs = array(); /** @access private */ var $_graph = null; /* }}} */ /* Constructor {{{ */ /** * * Constructor * * @access public */ function __construct() { } /* }}} */ /* getGraph {{{ */ /** * * Node graph getter * * @return Structures_Graph Graph where node is stored * @access public */ function &getGraph() { return $this->_graph; } /* }}} */ /* setGraph {{{ */ /** * * Node graph setter. This method should not be called directly. Use Graph::addNode instead. * * @param Structures_Graph Set the graph for this node. * @see Structures_Graph::addNode() * @access public */ function setGraph(&$graph) { $this->_graph =& $graph; } /* }}} */ /* getData {{{ */ /** * * Node data getter. * * Each graph node can contain a reference to one variable. This is the getter for that reference. * * @return mixed Data stored in node * @access public */ function &getData() { return $this->_data; } /* }}} */ /* setData {{{ */ /** * * Node data setter * * Each graph node can contain a reference to one variable. This is the setter for that reference. * * @return mixed Data to store in node * @access public */ function setData(&$data) { $this->_data =& $data; } /* }}} */ /* metadataKeyExists {{{ */ /** * * Test for existence of metadata under a given key. * * Each graph node can contain multiple 'metadata' entries, each stored under a different key, as in an * associative array or in a dictionary. This method tests whether a given metadata key exists for this node. * * @param string Key to test * @return boolean * @access public */ function metadataKeyExists($key) { return array_key_exists($key, $this->_metadata); } /* }}} */ /* getMetadata {{{ */ /** * * Node metadata getter * * Each graph node can contain multiple 'metadata' entries, each stored under a different key, as in an * associative array or in a dictionary. This method gets the data under the given key. If the key does * not exist, an error will be thrown, so testing using metadataKeyExists might be needed. * * @param string Key * @param boolean nullIfNonexistent (defaults to false). * @return mixed Metadata Data stored in node under given key * @see metadataKeyExists * @access public */ function &getMetadata($key, $nullIfNonexistent = false) { if (array_key_exists($key, $this->_metadata)) { return $this->_metadata[$key]; } else { if ($nullIfNonexistent) { $a = null; return $a; } else { $a = Pear::raiseError('Structures_Graph_Node::getMetadata: Requested key does not exist', STRUCTURES_GRAPH_ERROR_GENERIC); return $a; } } } /* }}} */ /* unsetMetadata {{{ */ /** * * Delete metadata by key * * Each graph node can contain multiple 'metadata' entries, each stored under a different key, as in an * associative array or in a dictionary. This method removes any data that might be stored under the provided key. * If the key does not exist, no error is thrown, so it is safe using this method without testing for key existence. * * @param string Key * @access public */ function unsetMetadata($key) { if (array_key_exists($key, $this->_metadata)) unset($this->_metadata[$key]); } /* }}} */ /* setMetadata {{{ */ /** * * Node metadata setter * * Each graph node can contain multiple 'metadata' entries, each stored under a different key, as in an * associative array or in a dictionary. This method stores data under the given key. If the key already exists, * previously stored data is discarded. * * @param string Key * @param mixed Data * @access public */ function setMetadata($key, &$data) { $this->_metadata[$key] =& $data; } /* }}} */ /* _connectTo {{{ */ /** @access private */ function _connectTo(&$destinationNode) { $this->_arcs[] =& $destinationNode; } /* }}} */ /* connectTo {{{ */ /** * * Connect this node to another one. * * If the graph is not directed, the reverse arc, connecting $destinationNode to $this is also created. * * @param Structures_Graph_Node Node to connect to * @access public */ function connectTo(&$destinationNode) { // We only connect to nodes if (!is_a($destinationNode, 'Structures_Graph_Node')) return Pear::raiseError('Structures_Graph_Node::connectTo received an object that is not a Structures_Graph_Node', STRUCTURES_GRAPH_ERROR_GENERIC); // Nodes must already be in graphs to be connected if ($this->_graph == null) return Pear::raiseError('Structures_Graph_Node::connectTo Tried to connect a node that is not in a graph', STRUCTURES_GRAPH_ERROR_GENERIC); if ($destinationNode->getGraph() == null) return Pear::raiseError('Structures_Graph_Node::connectTo Tried to connect to a node that is not in a graph', STRUCTURES_GRAPH_ERROR_GENERIC); // Connect here $this->_connectTo($destinationNode); // If graph is undirected, connect back if (!$this->_graph->isDirected()) { $destinationNode->_connectTo($this); } } /* }}} */ /* getNeighbours {{{ */ /** * * Return nodes connected to this one. * * @return array Array of nodes * @access public */ function getNeighbours() { return $this->_arcs; } /* }}} */ /* connectsTo {{{ */ /** * * Test wether this node has an arc to the target node * * @return boolean True if the two nodes are connected * @access public */ function connectsTo(&$target) { if (version_compare(PHP_VERSION, '5.0.0') >= 0) { return in_array($target, $this->getNeighbours(), true); } $copy = $target; $arcKeys = array_keys($this->_arcs); foreach($arcKeys as $key) { /* ZE1 chokes on this expression: if ($target === $arc) return true; so, we'll use more convoluted stuff */ $arc =& $this->_arcs[$key]; $target = true; if ($arc === true) { $target = false; if ($arc === false) { $target = $copy; return true; } } } $target = $copy; return false; } /* }}} */ /* inDegree {{{ */ /** * * Calculate the in degree of the node. * * The indegree for a node is the number of arcs entering the node. For non directed graphs, * the indegree is equal to the outdegree. * * @return integer In degree of the node * @access public */ function inDegree() { if ($this->_graph == null) return 0; if (!$this->_graph->isDirected()) return $this->outDegree(); $result = 0; $graphNodes =& $this->_graph->getNodes(); foreach (array_keys($graphNodes) as $key) { if ($graphNodes[$key]->connectsTo($this)) $result++; } return $result; } /* }}} */ /* outDegree {{{ */ /** * * Calculate the out degree of the node. * * The outdegree for a node is the number of arcs exiting the node. For non directed graphs, * the outdegree is always equal to the indegree. * * @return integer Out degree of the node * @access public */ function outDegree() { if ($this->_graph == null) return 0; return sizeof($this->_arcs); } /* }}} */ } ?>