perfect_match

perfect_match — min-cost perfect matching

Calling sequence

[cst,nmatch] = perfect_match(g,arcost)  

Parameters

g : graph list
arcost : integer row vector
cst : integer
nmatch : integer row vector

Description

perfect_match finds a perfect min-cost matching for the graph g. g must be an undirected graph with an even number of nodes. arcost is the vector of the (integer) costs of the arcs (the dimension of arcost is twice the number of edges of the graph). The output is the vector nmatch of the perfect matching and the corresponding cost cst.

Examples



ta=[27 27 3 12 11 12 27 26 26 25 25 24 23 23 21 22 21 20 19 18 18];
ta=[ta  16 15 15 14 12 9 10 6 9 17 8 17 10 20 11 23 23 12 18 28]; 
he=[ 1  2 2  4  5 11 13  1 25 22 24 22 22 19 13 13 14 16 16  9 16];
he=[he  10 10 11 12  2 6  5 5 7  8 7  9  6 11  4 18 13  3 28 17];
n=28;
g=make_graph('foo',0,n,ta,he);
xx=[46 120 207 286 366 453 543 544 473 387 300 206 136 250 346 408];
g('node_x')=[xx 527 443 306 326 196 139 264  55  58  46 118 513];
yy=[36  34  37  40  38  40  35 102 102  98  93  96 167 172 101 179];
g('node_y')=[yy 198 252 183 148 172 256 259 258 167 109 104 253];
show_graph(g);m2=2*size(ta,2);
arcost=round(100.*rand(1,m2));
[cst,nmatch] = perfect_match(g,arcost);
sp=sparse([ta' he'],[1:size(ta,2)]',[n,n]);
sp1=sparse([[1:n]' nmatch'],ones(1,size(nmatch,2))',[n,n]);
[ij,v,mn]=spget(sp.*sp1);
show_arcs(v');
 
  

See also

best_match