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 #define HUNGARIAN_MODE_MINIMIZE_COST 0
39 #define HUNGARIAN_MODE_MAXIMIZE_UTIL 1
41 #define HUNGARIAN_MATCH_NORMAL 0
42 #define HUNGARIAN_MATCH_PERFECT 1
44 typedef struct _hungarian_problem_t hungarian_problem_t;
47 * This method initialize the hungarian_problem structure and init
48 * the cost matrix (missing lines or columns are filled with 0).
50 * @param rows Number of rows in the given matrix
51 * @param cols Number of cols in the given matrix
52 * @param match_type The type of matching:
53 * HUNGARIAN_MATCH_PERFECT - every nodes matches another node
54 * HUNGARIAN_MATCH_NORMAL - matchings of nodes having no edge getting removed
55 * @return The problem object.
57 hungarian_problem_t *hungarian_new(int rows, int cols, int match_type);
60 * Adds an edge from left to right with some costs.
62 void hungarian_add(hungarian_problem_t *p, int left, int right, int cost);
65 * Removes the edge from left to right.
67 void hungarian_remv(hungarian_problem_t *p, int left, int right);
70 * Prepares the cost matrix dependent on the given mode.
72 * @param p The hungarian object
73 * @param mode HUNGARIAN_MODE_MAXIMIZE_UTIL or HUNGARIAN_MODE_MINIMIZE_COST (default)
75 void hungarian_prepare_cost_matrix(hungarian_problem_t *p, int mode);
78 * Destroys the hungarian object.
80 void hungarian_free(hungarian_problem_t *p);
83 * This method computes the optimal assignment.
84 * @param p The hungarian object
85 * @param assignment The final assignment
86 * @param final_cost The final costs
87 * @param cost_threshold Matchings with costs >= this limit will be removed (if limit > 0)
88 * @return 0 on success, negative number otherwise
90 int hungarian_solve(hungarian_problem_t *p, int *assignment, int *final_cost, int cost_threshold);
93 * Print the cost matrix.
94 * @param p The hungarian object
95 * @param cost_width The minimum field width of the costs
97 void hungarian_print_cost_matrix(hungarian_problem_t *p, int cost_width);