-
-
-
/* $Id$ */
-
/* a generic graph library. */
-/* Copyright (c) 2006 Darina Dimitrova, Arnaud Legrand.
- All rights reserved. */
+/* Copyright (c) 2006 Darina Dimitrova, Arnaud Legrand. */
+/* All rights reserved. */
/* This program is free software; you can redistribute it and/or modify it
* under the terms of the license (GNU LGPL) which comes with this package. */
#include "graph_private.h"
#include "xbt/graphxml_parse.h"
#include "xbt/dict.h"
+#include "xbt/heap.h"
+
+
+
XBT_LOG_NEW_DEFAULT_SUBCATEGORY(graph, xbt, "Graph");
-/** Constructor
- * \return a new graph
+/** @brief Constructor
+ * @return a new graph
*/
xbt_graph_t xbt_graph_new_graph(unsigned short int directed, void *data)
{
return graph;
}
+/** @brief add a node to the given graph */
xbt_node_t xbt_graph_new_node(xbt_graph_t g, void *data)
{
xbt_node_t node = NULL;
node = xbt_new0(struct xbt_node, 1);
node->data = data;
- node->in = xbt_dynar_new(sizeof(xbt_node_t), NULL);
- node->out = xbt_dynar_new(sizeof(xbt_node_t), NULL);
+ node->in = xbt_dynar_new(sizeof(xbt_edge_t), NULL);
+ node->out = xbt_dynar_new(sizeof(xbt_edge_t), NULL);
+ node->position_x = -1.0;
+ node->position_y = -1.0;
+
xbt_dynar_push(g->nodes, &node);
return node;
}
-
+/** @brief add an edge to the given graph */
xbt_edge_t xbt_graph_new_edge(xbt_graph_t g,
xbt_node_t src, xbt_node_t dst, void *data)
{
edge = xbt_new0(struct xbt_edge, 1);
xbt_dynar_push(src->out, &edge);
- xbt_dynar_push(dst->in, &edge);
+ if (g->directed)
+ xbt_dynar_push(dst->in, &edge);
+ else /* only the "out" field is used */
+ xbt_dynar_push(dst->out, &edge);
edge->data = data;
edge->src = src;
edge->dst = dst;
if (!g->directed)
{
- xbt_dynar_push(src->in, &edge);
- xbt_dynar_push(dst->out, &edge);
- }
+ xbt_dynar_push(src->in, &edge);
+ xbt_dynar_push(dst->out, &edge);
+ }
+
xbt_dynar_push(g->edges, &edge);
}
-/** Destructor
- * \param l poor victim
+/** @brief Destructor
+ * @param l: poor victim
*
* Free the graph structure.
*/
}
-
+/** @brief remove the given node from the given graph */
void xbt_graph_free_node(xbt_graph_t g, xbt_node_t n,
void_f_pvoid_t * node_free_function,
void_f_pvoid_t * edge_free_function)
return;
}
+/** @brief remove the given edge from the given graph */
void xbt_graph_free_edge(xbt_graph_t g, xbt_edge_t e,
void free_function(void *ptr))
{
{
if (edge == e)
{
- idx = __xbt_find_in_dynar(edge->dst->in,edge);
- xbt_dynar_remove_at(edge->dst->in, idx,NULL);
+ if (g->directed) {
+ idx = __xbt_find_in_dynar(edge->dst->in,edge);
+ xbt_dynar_remove_at(edge->dst->in, idx,NULL);
+ } else { /* only the out field is used */
+ idx = __xbt_find_in_dynar(edge->dst->out,edge);
+ xbt_dynar_remove_at(edge->dst->out, idx,NULL);
+ }
+
idx = __xbt_find_in_dynar(edge->src->out,edge);
xbt_dynar_remove_at(edge->src->out,idx,NULL);
- if (!g->directed)
- {
- idx = __xbt_find_in_dynar(edge->src->in,edge);
- xbt_dynar_remove_at(edge->src->in,idx,NULL);
- idx = __xbt_find_in_dynar(edge->dst->out,edge);
- xbt_dynar_remove_at(edge->dst->out,idx,NULL);
- }
+
xbt_dynar_cursor_rm(g->edges, &cursor);
free(edge);
break;
return -1;
}
+/** @brief Retrieve the graph's nodes as a dynar */
xbt_dynar_t xbt_graph_get_nodes(xbt_graph_t g)
{
return g->nodes;
}
+/** @brief Retrieve the graph's edges as a dynar */
xbt_dynar_t xbt_graph_get_edges(xbt_graph_t g)
{
return g->edges;
}
+/** @brief Retrieve the node at the source of the given edge */
xbt_node_t xbt_graph_edge_get_source(xbt_edge_t e)
{
return e->src;
}
+/** @brief Retrieve the node being the target of the given edge */
xbt_node_t xbt_graph_edge_get_target(xbt_edge_t e)
{
return e->dst;
}
+/** @brief Set the weight of the given edge */
void xbt_graph_edge_set_length(xbt_edge_t e, double length)
{
e->length = length;
}
-/*construct the adjacency matrix corresponding to a graph,
- the weights are the distances between nodes
+/** @brief construct the adjacency matrix corresponding to the given graph
+ *
+ * The weights are the distances between nodes
*/
double *xbt_graph_get_length_matrix(xbt_graph_t g)
{
return d;
}
-
+/** @brief Floyd-Warshall algorithm for shortest path finding
+ *
+ * From wikipedia:
+ *
+ * The Floyd–Warshall algorithm takes as input an adjacency matrix
+ * representation of a weighted, directed graph (V, E). The weight of a
+ * path between two vertices is the sum of the weights of the edges along
+ * that path. The edges E of the graph may have negative weights, but the
+ * graph must not have any negative weight cycles. The algorithm computes,
+ * for each pair of vertices, the minimum weight among all paths between
+ * the two vertices. The running time complexity is Θ(|V|3).
+ */
void xbt_floyd_algorithm(xbt_graph_t g, double *adj, double *d,
xbt_node_t * p)
{
# undef D
}
-/*computes all-pairs shortest paths*/
+/** @brief computes all-pairs shortest paths */
xbt_node_t *xbt_graph_shortest_paths(xbt_graph_t g)
{
xbt_node_t *p;
return r;
}
+/** @brief Extract a spanning tree of the given graph */
+xbt_edge_t* xbt_graph_spanning_tree_prim(xbt_graph_t g)
+{
+ int tree_size=0;
+ int tree_size_max=xbt_dynar_length(g->nodes)-1;
+ xbt_edge_t *tree = xbt_new0(xbt_edge_t,tree_size_max);
+ xbt_edge_t e,edge;
+ xbt_node_t node = NULL;
+ xbt_dynar_t edge_list = NULL;
+ xbt_heap_t heap = xbt_heap_new(10,NULL);
+ int cursor;
+
+ xbt_assert0(!(g->directed),
+ "Spanning trees do not make sense on directed graphs");
+
+ xbt_dynar_foreach(g->nodes, cursor, node) {
+ node->xbtdata = NULL;
+ }
+
+ node = xbt_dynar_getfirst_as(g->nodes,xbt_node_t);
+ node->xbtdata = (void*) 1;
+ edge_list = node->out;
+ xbt_dynar_foreach(edge_list, cursor, e)
+ xbt_heap_push(heap,e, -(e->length));
+
+ while((edge=xbt_heap_pop(heap))) {
+ if((edge->src->xbtdata) && (edge->dst->xbtdata)) continue;
+ tree[tree_size++]=edge;
+ if(!(edge->src->xbtdata)) {
+ edge->src->xbtdata = (void*) 1;
+ edge_list = edge->src->out;
+ xbt_dynar_foreach(edge_list, cursor, e) {
+ xbt_heap_push(heap,e, -(e->length));
+ }
+ } else {
+ edge->dst->xbtdata = (void*) 1;
+ edge_list = edge->dst->out;
+ xbt_dynar_foreach(edge_list, cursor, e) {
+ xbt_heap_push(heap,e, -(e->length));
+ }
+ }
+ if(tree_size==tree_size_max) break;
+ }
+
+ xbt_heap_free(heap);
+
+ return tree;
+}
+
+/** @brief Topological sort on the given graph
+ *
+ * From wikipedia:
+ *
+ * In graph theory, a topological sort of a directed acyclic graph (DAG) is
+ * a linear ordering of its nodes which is compatible with the partial
+ * order R induced on the nodes where x comes before y (xRy) if there's a
+ * directed path from x to y in the DAG. An equivalent definition is that
+ * each node comes before all nodes to which it has edges. Every DAG has at
+ * least one topological sort, and may have many.
+ */
+xbt_node_t* xbt_graph_topo_sort(xbt_graph_t g)
+{
+
+ xbt_node_t* sorted;
+ int cursor,idx;
+ xbt_node_t node;
+ unsigned long n;
+
+ n= xbt_dynar_length(g->nodes);
+ idx=n-1;
+
+ sorted=xbt_malloc(n*sizeof(xbt_node_t));
+ xbt_dynar_foreach(g->nodes,cursor , node)
+ {
+ node->xbtdata=xbt_new0(int,1);
+ }
+
+ xbt_dynar_foreach(g->nodes,cursor , node)
+ {
+ xbt_graph_depth_visit(g,node,sorted,&idx);
+ }
+ xbt_dynar_foreach(g->nodes, cursor, node)
+ {
+ node->xbtdata = NULL;
+ }
+ return sorted;
+}
+/** @brief First-depth graph traversal */
+void xbt_graph_depth_visit(xbt_graph_t g,xbt_node_t n,xbt_node_t* sorted,int* idx )
+{
+ int cursor;
+ xbt_edge_t edge;
+
+ if (*((int*)(n->xbtdata))==ALREADY_EXPLORED)
+ return;
+ else if (*((int*)(n->xbtdata))==CURRENTLY_EXPLORING)
+ THROW0(0,0,"There is a cycle");
+ else
+ {
+ *((int*)(n->xbtdata))=CURRENTLY_EXPLORING;
+
+ xbt_dynar_foreach(n->out,cursor, edge)
+ {
+ xbt_graph_depth_visit(g,edge->dst,sorted,idx);
+ }
+
+ *((int*)(n->xbtdata))=ALREADY_EXPLORED;
+ sorted[(*idx)--]=n;
+ }
+}
+
+/********************* Import and Export ******************/
static xbt_graph_t parsed_graph = NULL;
static xbt_dict_t parsed_nodes = NULL;
+static void *(*__parse_node_label_and_data)(xbt_node_t, const char*, const char*) = NULL;
+static void *(*__parse_edge_label_and_data)(xbt_edge_t, const char*, const char*) = NULL;
static void __parse_graph_begin(void)
{
DEBUG0("<graph>");
+ if(A_graphxml_graph_isDirected == A_graphxml_graph_isDirected_true)
+ parsed_graph = xbt_graph_new_graph(1, NULL);
+ else parsed_graph = xbt_graph_new_graph(0, NULL);
+
+ parsed_nodes = xbt_dict_new();
}
+
static void __parse_graph_end(void)
{
+ xbt_dict_free(&parsed_nodes);
DEBUG0("</graph>");
}
static void __parse_node(void)
{
xbt_node_t node =
- xbt_graph_new_node(parsed_graph, (void *) A_graphxml_node_name);
+ xbt_graph_new_node(parsed_graph, NULL);
- xbt_dict_set(parsed_nodes, A_graphxml_node_name, (void *) node, NULL);
+ DEBUG1("<node name=\"%s\"/>", A_graphxml_node_name);
+ if(__parse_node_label_and_data)
+ node->data = __parse_node_label_and_data(node,A_graphxml_node_label,
+ A_graphxml_node_data);
+ xbt_graph_parse_get_double(&(node->position_x),A_graphxml_node_position_x);
+ xbt_graph_parse_get_double(&(node->position_y),A_graphxml_node_position_y);
- DEBUG1("<node label=\"%s\"/>", (char *) (node->data));
+ xbt_dict_set(parsed_nodes, A_graphxml_node_name, (void *) node, NULL);
}
+
static void __parse_edge(void)
{
- xbt_edge_t edge = xbt_graph_new_edge(parsed_graph,
- xbt_dict_get(parsed_nodes,
- A_graphxml_edge_source),
- xbt_dict_get(parsed_nodes,
- A_graphxml_edge_target),
- (void *) A_graphxml_edge_name);
+ xbt_edge_t edge =
+ xbt_graph_new_edge(parsed_graph,
+ xbt_dict_get(parsed_nodes,A_graphxml_edge_source),
+ xbt_dict_get(parsed_nodes,A_graphxml_edge_target),
+ NULL);
+
+ if(__parse_edge_label_and_data)
+ edge->data = __parse_edge_label_and_data(edge,A_graphxml_edge_label,
+ A_graphxml_edge_data);
- xbt_graph_edge_set_length(edge, atof(A_graphxml_edge_length));
+ xbt_graph_parse_get_double(&(edge->length),A_graphxml_edge_length);
- DEBUG4("<edge name=\"%s\" source=\"%s\" target=\"%s\" length=\"%f\"/>",
- (char *) edge->data,
+ DEBUG3("<edge source=\"%s\" target=\"%s\" length=\"%f\"/>",
(char *) (edge->src)->data,
(char *) (edge->dst)->data,
xbt_graph_edge_get_length(edge));
}
-xbt_graph_t xbt_graph_read(const char *filename)
+/** @brief Import a graph from a file following the GraphXML format */
+xbt_graph_t xbt_graph_read(const char *filename,
+ void *(node_label_and_data)(xbt_node_t, const char*, const char*),
+ void *(edge_label_and_data)(xbt_edge_t, const char*, const char*))
{
- xbt_graph_t graph = xbt_graph_new_graph(1, NULL);
- parsed_graph = graph;
- parsed_nodes = xbt_dict_new();
+ xbt_graph_t graph = NULL;
+ __parse_node_label_and_data = node_label_and_data;
+ __parse_edge_label_and_data = edge_label_and_data;
xbt_graph_parse_reset_parser();
ETag_graphxml_node_fun = __parse_node;
ETag_graphxml_edge_fun = __parse_edge;
-
xbt_graph_parse_open(filename);
xbt_assert1((!xbt_graph_parse()), "Parse error in %s", filename);
xbt_graph_parse_close();
- xbt_dict_free(&parsed_nodes);
-
+ graph = parsed_graph;
parsed_graph = NULL;
+
return graph;
}
+/** @brief Export the given graph in the GraphViz formatting for visualization */
void xbt_graph_export_graphviz(xbt_graph_t g, const char *filename,
const char *(node_name) (xbt_node_t),
const char *(edge_name) (xbt_edge_t))
fclose(file);
}
+/** @brief Export the given graph in the GraphXML format */
void xbt_graph_export_graphxml(xbt_graph_t g, const char *filename,
const char *(node_name)(xbt_node_t),
- const char *(edge_name)(xbt_edge_t))
+ const char *(edge_name)(xbt_edge_t),
+ const char *(node_data_print)(void *),
+ const char *(edge_data_print)(void *))
{
int cursor = 0;
xbt_node_t node = NULL;
fprintf(file,"<?xml version='1.0'?>\n");
fprintf(file,"<!DOCTYPE graph SYSTEM \"graphxml.dtd\">\n");
- fprintf(file,"<graph>\n");
+ if(g->directed) fprintf(file,"<graph isDirected=\"true\">\n");
+ else fprintf(file,"<graph isDirected=\"false\">\n");
xbt_dynar_foreach(g->nodes, cursor, node) {
fprintf(file," <node name=\"%p\" ", node);
if((node_name)&&((name=node_name(node)))) fprintf(file,"label=\"%s\" ",name);
+ if((node_data_print)&&((name=node_data_print(node->data))))
+ fprintf(file,"data=\"%s\" ",name);
fprintf(file,">\n");
}
xbt_dynar_foreach(g->edges, cursor, edge) {
fprintf(file," <edge source=\"%p\" target =\"%p\" ",
edge->src, edge->dst );
if((edge_name)&&((name=edge_name(edge)))) fprintf(file,"label=\"%s\" ",name);
+ if(edge->length>=0.0) fprintf(file,"length=\"%g\" ",edge->length);
+ if((edge_data_print)&&((name=edge_data_print(edge->data))))
+ fprintf(file,"data=\"%s\" ",name);
fprintf(file,">\n");
}
fprintf(file,"</graph>\n");
