1 #include <iostream> 2 #include <Eigen/Dense> 3 4 using namespace std; 5 using namespace Eigen; 6 main()7int main() 8 { 9 Matrix2f A, b; 10 LLT<Matrix2f> llt; 11 A << 2, -1, -1, 3; 12 b << 1, 2, 3, 1; 13 cout << "Here is the matrix A:\n" << A << endl; 14 cout << "Here is the right hand side b:\n" << b << endl; 15 cout << "Computing LLT decomposition..." << endl; 16 llt.compute(A); 17 cout << "The solution is:\n" << llt.solve(b) << endl; 18 A(1,1)++; 19 cout << "The matrix A is now:\n" << A << endl; 20 cout << "Computing LLT decomposition..." << endl; 21 llt.compute(A); 22 cout << "The solution is now:\n" << llt.solve(b) << endl; 23 } 24