-- FreeFem++ v4.6 (Thu Apr  2 15:47:38 CEST 2020 - git v4.6)
 Load: lg_fem lg_mesh lg_mesh3 eigenvalue 
    1 : //  mesh_points.edp
    2 : //
    3 : //  Discussion:
    4 : //
    5 : //    The file "mesh_points_input.txt" lists points that define the boundary.
    6 : //
    7 : //    Create the corresponding region and mesh it.
    8 : //
    9 : //  Location:
   10 : //
   11 : //    http://people.sc.fsu.edu/~jburkardt/freefem_src/mesh_points/mesh_points.edp
   12 : //
   13 : //  Modified:
   14 : //
   15 : //    01 August 2015
   16 : //
   17 : cout << "\n";
   18 : cout << "MESH_POINTS:\n";
   19 : cout << "  FreeFem++ version.\n";
   20 : cout << "  Read a file of point coordinates that outline a
  ... :  region.\n";
   21 : cout << "  Create the region and mesh it.\n";
   22 : //
   23 : //  Attach the file as input.
   24 : //
   25 : string filename = "mesh_points_input.txt";
   26 : 
   27 : ifstream file ( filename );
   28 : cout << "\n";
   29 : cout << "Reading data from '" << filename << "'\n";
   30 : //
   31 : //  Read the number of points.
   32 : //
   33 : int nn = 0; 
   34 : file >> nn;
   35 : cout << "  Number of nodes = "<< nn << endl;
   36 : //
   37 : //  Read the X and Y coordinates.
   38 : //
   39 : real[int] Gxx(nn);
   40 : real[int] Gyy(nn);
   41 : for ( int i = 0; i < nn; i++ ) 
   42 : {
   43 :   file >> Gxx[i] >> Gyy[i];
   44 : }
   45 : //
   46 : //  List the nodes.
   47 : //
   48 : cout << "\n";
   49 : cout << "  Boundary nodes:\n";
   50 : cout << "\n";
   51 : for ( int i = 0; i < nn; i++ ) 
   52 : {
   53 :   cout << "  " << i
   54 :        << "  " << Gxx[i]
   55 :        << "  " << Gyy[i] << endl;
   56 : }
   57 : //
   58 : //  Create the corresponding border.
   59 : //
   60 : border Gsup ( t = 0, nn - 1 ) 
   61 : {
   62 :   int i = min ( int ( t ), Gxx.n - 2 ); 
   63 :   real t1 = t - i;
   64 :   x = Gxx[i] * ( 1.0 - ( t - i ) ) + Gxx[i+1] * ( t - i ); 
   65 :   y = Gyy[i] * ( 1.0 - ( t - i ) ) + Gyy[i+1] * ( t - i ); 
   66 :   label = i + 1; 
   67 : }
   68 : plot ( Gsup ( nn * 20 ), wait = 1, ps = "mesh_points_border.ps", 
   69 :   cmm = "mesh_points boundary" );
   70 : //
   71 : //  Create the mesh.
   72 : //
   73 : mesh Th = buildmesh ( Gsup ( nn * 20 ) );
   74 : plot ( Th, wait = 1, ps = "mesh_points_mesh.ps", cmm = "mesh_points mesh" );
   75 : //
   76 : //  Solve a problem on this mesh.
   77 : //
   78 : //  Define the finite element space.
   79 : //
   80 : fespace Vh ( Th, P1 );
   81 : //
   82 : //  Define test and trial functions.
   83 : //
   84 : Vh u;
   85 : Vh v;
   86 : //
   87 : //  Define and solve the problem.
   88 : //
   89 : solve Problem1 ( u, v ) =
   90 :   int2d ( Th )( dx(u) * dx(v) + dy(u) * dy(v) ) 
   91 : + int2d ( Th ) ( -v )
   92 : + on ( 1, u = 0 )
   93 : + on ( 2, u = 1 )
   94 : + on ( 3, u = 0 )
   95 : + on ( 4, u = 0 );
   96 : 
   97 : plot ( u, wait = 1, fill = 1, ps = "mesh_points_uh.ps", cmm = "mesh points solution" );
   98 : //
   99 : //  Terminate.
  100 : //
  101 : cout << "\n";
  102 : cout << "mesh_points:\n";
  103 : cout << "  Normal end of execution.\n";
  104 : 
  105 :  sizestack + 1024 =2008  ( 984 )


MESH_POINTS:
  FreeFem++ version.
  Read a file of point coordinates that outline a region.
  Create the region and mesh it.

Reading data from 'mesh_points_input.txt'
  Number of nodes = 7

  Boundary nodes:

  0  0  0
  1  1  0
  2  1  0.5
  3  0.5  0.5
  4  0.5  1
  5  0  1
  6  0  0
  --  mesh:  Nb of Triangles =   1972, Nb of Vertices 1057
  -- Solve : 
          min 7.63821e-33  max 1

mesh_points:
  Normal end of execution.
times: compile 0.005083s, execution 0.712747s,  mpirank:0
 CodeAlloc : nb ptr  3712,  size :478760 mpirank: 0
Ok: Normal End