pgrouting::graph Namespace Reference

boost::graph simplified to pgRouting needs This class gives the handling basics of a boost::graph of kind G where G: can be an undirected graph or a directed graph. More...

Classes
class	Pgr_base_graph
class	Pgr_contractionGraph
class	Pgr_lineGraph
class	Pgr_lineGraphFull
class	PgrCostFlowGraph
class	PgrDirectedChPPGraph
class	PgrFlowGraph

Typedefs
using	CHDirectedGraph = Pgr_contractionGraph< boost::adjacency_list< boost::listS, boost::vecS, boost::bidirectionalS, CH_vertex, CH_edge > >
using	CHUndirectedGraph = Pgr_contractionGraph< boost::adjacency_list< boost::listS, boost::vecS, boost::undirectedS, CH_vertex, CH_edge > >

Detailed Description

boost::graph simplified to pgRouting needs This class gives the handling basics of a boost::graph of kind G where G: can be an undirected graph or a directed graph.

Requiremets:

A vertex class T_V

Current Available vertex classes:

• Basic_vertex
• XY_vertex

An edge class T_E

Current Available edge classes:

• Basic_edge

extract_vertices function

Data obtained from postgresql is stored in A C array of pgr_edge_t type.

std::vector< T_V >
extract_vertices(pgr_edge_t *, size_t)

Data obtained from postgresql is stored in o a vector container.

std::vector< T_V >
extract_vertices(std::vector< pgr_edge_t >)

Boost Graph

The code is prepared to be used for:

• boost::adjacency_list graph type
• boost::undirectedS when the graph is UNDIRECTED
• boost::bidirectionalS when the graph is DIRECTED

  boost::adjacency_list
  < boost::vecS,  // not tested with other values
  boost::vecS,  // not tested with other values
  boost::undirectedS,  // USinG UNDIRECTED
  Basic_vertex,  // the vertex class
  Basic_edge >   // the edge class

Example Usage:

For this example we will use:

• Basic_vertex
• Basic_edge
• pgr_edge_t

Create Graph type

typedef typename
graph::Pgr_base_graph <
boost::adjacency_list <
boost::vecS,
    boost::vecS,
    boost::bidirectionalS,
    Basic_vertex,
    Basic_edge >,
    Basic_vertex,
    Basic_edge >
    DirectedGraph;

Initializing the graph

Graph initialization is for seting the Vertices of the graph. TODO discuss if also the edges Vector of unique vertices of the graph

size_t total_edges;
pgr_edge_t *my_edges = NULL;
pgr_get_edges(edges_sql, &my_edges, &total_tuples);
std::vector< Basic_Vertex > vertices(pgrouting::extract_vertices(my_edges));

There are several ways to initialize the graph

// 1. Initializes an empty graph
pgrouting::DirectedGraph digraph(gType);
// 2. Initializes a graph based on the vertices
pgrouting::DirectedGraph digraph(
    verices,
    gType);
vertices.clear();
3. Initializes a graph based on the extracted vertices
pgrouting::DirectedGraph digraph(
    pgrouting::extract_vertices(my_edges, total_edges);
    gType);
4. Initializes a graph based on the extracted vertices
pgrouting::DirectedGraph digraph(
    pgrouting::extract_vertices(my_edges);
    gType);

1. Initializes an empty graph
   • vertices vector size is 0
2. Initializes a graph based on the vertices:
   • vertices vector size is vertices.size()
   • the vertices are inserted
   • vertices container can be clared to free memory
3. Initializes a graph based on the vertices extracted
   • from edges stored on a C array
   • the vertices are inserted
4. Initializes a graph based on the vertices extracted
   • from edges stored on a vector
   • the vertices are inserted

Fill the graph

After initializing the graph with the vertices, the edges can be added.

// inserting edges from a C array
digraph.insert_edges(my_edges, total_edges);
// adding more edges to the graph from a vector container
digraph.insert_edges(new_edges);

Typedef Documentation

CHDirectedGraph

using pgrouting::graph::CHDirectedGraph = typedef Pgr_contractionGraph< boost::adjacency_list < boost::listS, boost::vecS, boost::bidirectionalS, CH_vertex, CH_edge> >

Definition at line 56 of file ch_graphs.hpp.

CHUndirectedGraph

using pgrouting::graph::CHUndirectedGraph = typedef Pgr_contractionGraph < boost::adjacency_list < boost::listS, boost::vecS, boost::undirectedS, CH_vertex, CH_edge> >

Definition at line 51 of file ch_graphs.hpp.