1 /********************************************************************
2 ********************************************************************
4 ** libhungarian by Cyrill Stachniss, 2004
6 ** Added to libFirm by Christian Wuerdig, 2006
7 ** Added several options for not-perfect matchings.
9 ** Solving the Minimum Assignment Problem using the
12 ** ** This file may be freely copied and distributed! **
14 ** Parts of the used code was originally provided by the
15 ** "Stanford GraphGase", but I made changes to this code.
16 ** As asked by the copyright node of the "Stanford GraphGase",
17 ** I hereby proclaim that this file are *NOT* part of the
18 ** "Stanford GraphGase" distribution!
20 ** This file is distributed in the hope that it will be useful,
21 ** but WITHOUT ANY WARRANTY; without even the implied
22 ** warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR
25 ********************************************************************
26 ********************************************************************/
30 * @brief Solving the Minimum Assignment Problem using the Hungarian Method.
33 #ifndef FIRM_ADT_HUNGARIAN_H
34 #define FIRM_ADT_HUNGARIAN_H
38 typedef enum match_type_t {
39 HUNGARIAN_MATCH_NORMAL, /**< ever nodes matches another node */
40 HUNGARIAN_MATCH_PERFECT /**< matchings of nodes having no edge getting
44 typedef enum hungarian_mode_t {
45 HUNGARIAN_MODE_MINIMIZE_COST,
46 HUNGARIAN_MODE_MAXIMIZE_UTIL
49 typedef struct hungarian_problem_t hungarian_problem_t;
52 * This method initialize the hungarian_problem structure and init
53 * the cost matrix (missing lines or columns are filled with 0).
55 * @param rows Number of rows in the given matrix
56 * @param cols Number of cols in the given matrix
57 * @param match_type The type of matching
58 * @return The problem object.
60 FIRM_API hungarian_problem_t *hungarian_new(unsigned rows, unsigned cols,
61 match_type_t match_type);
64 * Adds an edge from left to right with some costs.
66 FIRM_API void hungarian_add(hungarian_problem_t *p, unsigned left,
67 unsigned right, int cost);
70 * Removes the edge from left to right.
72 FIRM_API void hungarian_remove(hungarian_problem_t *p, unsigned left,
76 * Prepares the cost matrix dependent on the given mode.
78 * @param p The hungarian object
79 * @param mode specify wether to minimize or maximize the costs
81 FIRM_API void hungarian_prepare_cost_matrix(hungarian_problem_t *p,
82 hungarian_mode_t mode);
85 * Destroys the hungarian object.
87 FIRM_API void hungarian_free(hungarian_problem_t *p);
90 * This method computes the optimal assignment.
91 * @param p The hungarian object
92 * @param assignment The final assignment
93 * @param final_cost The final costs
94 * @param cost_threshold Matchings with costs >= this limit will be removed (if limit > 0)
95 * @return 0 on success, negative number otherwise
97 FIRM_API int hungarian_solve(hungarian_problem_t *p, unsigned *assignment,
98 int *final_cost, int cost_threshold);
101 * Print the cost matrix.
102 * @param p The hungarian object
103 * @param cost_width The minimum field width of the costs
105 FIRM_API void hungarian_print_cost_matrix(hungarian_problem_t *p,