PGROUTING  3.2
bellman_ford_driver.cpp
Go to the documentation of this file.
1 /*PGR-GNU*****************************************************************
2 File: bellman_ford_driver.cpp
3 
4 Generated with Template by:
5 Copyright (c) 2015 pgRouting developers
7 
8 Function's developer:
9 Copyright (c) 2018 Sourabh Garg
11 
12 ------
13 
14 This program is free software; you can redistribute it and/or modify
15 it under the terms of the GNU General Public License as published by
16 the Free Software Foundation; either version 2 of the License, or
17 (at your option) any later version.
18 
19 This program is distributed in the hope that it will be useful,
20 but WITHOUT ANY WARRANTY; without even the implied warranty of
21 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
22 GNU General Public License for more details.
23 
24 You should have received a copy of the GNU General Public License
25 along with this program; if not, write to the Free Software
26 Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
27 
28  ********************************************************************PGR-GNU*/
29 
31 
32 #include <sstream>
33 #include <deque>
34 #include <vector>
35 #include <algorithm>
36 #include <string>
37 
39 
40 #include "cpp_common/pgr_alloc.hpp"
41 #include "cpp_common/pgr_assert.h"
42 
43 
44 /* Bellman Ford Shortest Path */
45 /************************************************************
46  EDGE_SQL,
47  ANYARRAY,
48  ANYARRAY,
49  directed BOOLEAN DEFAULT true,
50  ***********************************************************/
51 
52 template < class G >
53 std::deque< Path >
55  G &graph,
56  std::vector <pgr_combination_t> &combinations,
57  std::vector < int64_t > sources,
58  std::vector < int64_t > targets,
59  std::string &log,
60  bool only_cost = false) {
61  std::sort(sources.begin(), sources.end());
62  sources.erase(
63  std::unique(sources.begin(), sources.end()),
64  sources.end());
65 
66  std::sort(targets.begin(), targets.end());
67  targets.erase(
68  std::unique(targets.begin(), targets.end()),
69  targets.end());
70 
71  Pgr_bellman_ford< G > fn_bellman_ford;
72  auto paths = combinations.empty() ?
73  fn_bellman_ford.bellman_ford(graph, sources, targets, only_cost)
74  : fn_bellman_ford.bellman_ford(graph, combinations, only_cost);
75  log += fn_bellman_ford.get_log();
76  for (auto &p : paths) {
77  p.recalculate_agg_cost();
78  }
79  return paths;
80 }
81 
82 void
84  pgr_edge_t *data_edges,
85  size_t total_edges,
86  pgr_combination_t *combinations,
87  size_t total_combinations,
88  int64_t *start_vidsArr,
89  size_t size_start_vidsArr,
90  int64_t *end_vidsArr,
91  size_t size_end_vidsArr,
92  bool directed,
93  bool only_cost,
94 
95  General_path_element_t **return_tuples,
96  size_t *return_count,
97  char ** log_msg,
98  char ** notice_msg,
99  char ** err_msg) {
100  std::ostringstream log;
101  std::ostringstream err;
102  std::ostringstream notice;
103  try {
104  pgassert(!(*log_msg));
105  pgassert(!(*notice_msg));
106  pgassert(!(*err_msg));
107  pgassert(!(*return_tuples));
108  pgassert(*return_count == 0);
109  pgassert(total_edges != 0);
110  pgassert(data_edges);
111  pgassert((start_vidsArr && end_vidsArr) || combinations);
112  pgassert((size_start_vidsArr && size_end_vidsArr) || total_combinations);
113 
114  graphType gType = directed? DIRECTED: UNDIRECTED;
115 
116  log << "Inserting vertices into a c++ vector structure";
117  std::vector<int64_t>
118  start_vertices(start_vidsArr, start_vidsArr + size_start_vidsArr);
119  std::vector< int64_t >
120  end_vertices(end_vidsArr, end_vidsArr + size_end_vidsArr);
121  std::vector< pgr_combination_t >
122  combinations_vector(combinations, combinations + total_combinations);
123 
124  std::deque< Path >paths;
125  std::string logstr;
126  if (directed) {
127  log << "Working with directed Graph\n";
128  pgrouting::DirectedGraph digraph(gType);
129  digraph.insert_edges(data_edges, total_edges);
130  paths = pgr_bellman_ford(digraph,
131  combinations_vector,
132  start_vertices,
133  end_vertices,
134  logstr,
135  only_cost);
136  } else {
137  log << "Working with Undirected Graph\n";
138  pgrouting::UndirectedGraph undigraph(gType);
139  undigraph.insert_edges(data_edges, total_edges);
140  paths = pgr_bellman_ford(
141  undigraph,
142  combinations_vector,
143  start_vertices,
144  end_vertices,
145  logstr,
146  only_cost);
147  }
148  log<< logstr;
149  size_t count(0);
150  count = count_tuples(paths);
151 
152  if (count == 0) {
153  (*return_tuples) = NULL;
154  (*return_count) = 0;
155  notice <<
156  "No paths found";
157  *log_msg = pgr_msg(notice.str().c_str());
158  return;
159  }
160 
161  (*return_tuples) = pgr_alloc(count, (*return_tuples));
162  log << "\nConverting a set of paths into the tuples";
163  (*return_count) = (collapse_paths(return_tuples, paths));
164 
165  *log_msg = log.str().empty()?
166  *log_msg :
167  pgr_msg(log.str().c_str());
168  *notice_msg = notice.str().empty()?
169  *notice_msg :
170  pgr_msg(notice.str().c_str());
171  } catch (AssertFailedException &except) {
172  (*return_tuples) = pgr_free(*return_tuples);
173  (*return_count) = 0;
174  err << except.what();
175  *err_msg = pgr_msg(err.str().c_str());
176  *log_msg = pgr_msg(log.str().c_str());
177  } catch (std::exception &except) {
178  (*return_tuples) = pgr_free(*return_tuples);
179  (*return_count) = 0;
180  err << except.what();
181  *err_msg = pgr_msg(err.str().c_str());
182  *log_msg = pgr_msg(log.str().c_str());
183  } catch(...) {
184  (*return_tuples) = pgr_free(*return_tuples);
185  (*return_count) = 0;
186  err << "Caught unknown exception!";
187  *err_msg = pgr_msg(err.str().c_str());
188  *log_msg = pgr_msg(log.str().c_str());
189  }
190 }
pgr_alloc
T * pgr_alloc(std::size_t size, T *ptr)
allocates memory
Definition: pgr_alloc.hpp:66
count_tuples
size_t count_tuples(const std::deque< Path > &paths)
Definition: basePath_SSEC.cpp:387
pgr_edge_t
Definition: pgr_edge_t.h:37
pgr_msg
char * pgr_msg(const std::string &msg)
Definition: pgr_alloc.cpp:30
AssertFailedException::what
virtual const char * what() const
Definition: pgr_assert.cpp:67
collapse_paths
size_t collapse_paths(General_path_element_t **ret_path, const std::deque< Path > &paths)
Definition: basePath_SSEC.cpp:310
Pgr_bellman_ford::bellman_ford
Path bellman_ford(G &graph, int64_t start_vertex, int64_t end_vertex, bool only_cost=false)
BellmanFord 1 to 1.
Definition: pgr_bellman_ford.hpp:62
pgassert
#define pgassert(expr)
Uses the standard assert syntax.
Definition: pgr_assert.h:94
UNDIRECTED
@ UNDIRECTED
Definition: graph_enum.h:30
pgrouting::graph::Pgr_base_graph::insert_edges
void insert_edges(const T *edges, size_t count)
Inserts count edges of type T into the graph.
Definition: pgr_base_graph.hpp:357
pgr_alloc.hpp
Pgr_bellman_ford
Definition: pgr_bellman_ford.hpp:53
pgr_bellman_ford
std::deque< Path > pgr_bellman_ford(G &graph, std::vector< pgr_combination_t > &combinations, std::vector< int64_t > sources, std::vector< int64_t > targets, std::string &log, bool only_cost=false)
Definition: bellman_ford_driver.cpp:54
pgrouting::Pgr_messages::get_log
std::string get_log() const
get_log
Definition: pgr_messages.cpp:36
do_pgr_bellman_ford
void do_pgr_bellman_ford(pgr_edge_t *data_edges, size_t total_edges, pgr_combination_t *combinations, size_t total_combinations, int64_t *start_vidsArr, size_t size_start_vidsArr, int64_t *end_vidsArr, size_t size_end_vidsArr, bool directed, bool only_cost, General_path_element_t **return_tuples, size_t *return_count, char **log_msg, char **notice_msg, char **err_msg)
Definition: bellman_ford_driver.cpp:83
pgr_combination_t
Definition: pgr_combination_t.h:43
graphType
graphType
Definition: graph_enum.h:30
pgr_assert.h
An assert functionality that uses C++ throw().
DIRECTED
@ DIRECTED
Definition: graph_enum.h:30
General_path_element_t
Definition: general_path_element_t.h:37
pgr_bellman_ford.hpp
pgrouting::alphashape::G
graph::Pgr_base_graph< BG, XY_vertex, Basic_edge > G
Definition: pgr_alphaShape.h:56
pgr_free
T * pgr_free(T *ptr)
Definition: pgr_alloc.hpp:77
pgrouting::graph::Pgr_base_graph
Definition: pgr_base_graph.hpp:168
bellman_ford_driver.h
AssertFailedException
Extends std::exception and is the exception that we throw if an assert fails.
Definition: pgr_assert.h:139