superlu.edp

FreeFem++可以生成高质量的有限元网格。可以用于流体力学

load "SuperLU"
verbosity=0;
for(int i=0;i<3;++i)
{
  {
    matrix A = 
      [[ 0,  1,  0, 10],
       [ 0,  0,  2,  0],
       [ 0,  0,  0,  3],
       [ 4,  0,  0,  0]];
    real[int] xx = [ 4,1,2,3], x(4), b(4); // xb(4),bbb(4);
    b=A*xx;
    cout << "b="  << b  << endl;
    cout << "xx=" << xx << endl;
    cout << "A="  << A  << endl;
    set(A,solver=sparsesolver); 
    x = A^-1*b;	
    cout << "x=" << endl; cout << x << endl;
    cout << "A="  << A  << endl;	
  }
  
  {
    matrix<complex> A = 
      [[  0, 1i,  0, 10],
       [  0,  0, 2i,  0],
       [  0,  0,  0, 3i],
       [ 4i,  0,  0,  0]];
    complex[int] xx = [ 4i,1i,2i,3i], x(4), b(4);
    b = A*xx;
    cout << "b="  << b << endl;
    cout << "xx=" << xx << endl;
    set(A,solver=sparsesolver);
    x = A^-1*b;
    cout << "x=" << endl; cout << x << endl;
  }
  if(i==0)defaulttoGMRES();
  if(i==1)defaultsolver();
  
}