1 /*******************************************************
 2  *  This file is part of the FreeFEM tutorial made by  *
 3  *      Pierre Jolivet <pierre@joliv.et>               *
 4  *                                                     *
 5  *  See https://joliv.et/FreeFem-tutorial for more     *
 6  *                                                     *
 7  *   Description: mesh partitioning                    *
 8  *******************************************************/
  
10 load "metis"
11 border a(t=0, pi) { x=cos(t); y=sin(t); label=1; }
12 border b(t=pi, 2*pi) { x=cos(t); y=sin(t); label=2; }
13 mesh Th = buildmesh(a(100) + b(100));
14 fespace Ph(Th, P0);
15 Ph part;
16 metisdual(part[], Th, 32);
17 plot(part, value = 1, fill = 1, wait = 1, cmm = "partitioning");
18 for(int i = 0; i < 32; ++i) {
19     Ph vis = (abs(part - i) < 1e-12) * 10;
20     int elt = 0;
21     for(int j = 0; j < Ph.ndof; ++j)
22         if(vis[][j] > 1e-12)
23             ++elt;
24     plot(vis, fill = 1, cmm = "partition " + i +", " + elt + " element(s)", wait = 1, nbiso = 32);
25 }