test_matrix_algebra2.cpp

 
#include <Pds/Ra>
    
int main(void)
{
    Pds::Matrix A(  "12 -51   4\n"
                    " 6 167 -68\n"
                    "-4  24 -41");
    
    A.Print("A:\n");
    
    Pds::Matrix Q(A.Size());
    Pds::Matrix R(A.Ncol());
    
    A.QR(Q,R);
    std::cout<<"A.QR(Q,R):"<<std::endl;
    
    Q.Print("Q:\n");
    R.Print("R:\n");
    
    (Q*R).Print("Q*R:\n");
    
    Pds::Matrix H;
    A=" 4 1 -2  2\n"
      " 1 2  0  1\n"
      "-2 0  3 -2\n"
      " 2 1 -2 -1";
    H=A.HessenbergReduction();
    H.Round(9).Print("H:\n");
    
    A="722.59415501536  14.961544421002  11.686206559208\n"  
      "14.961544421002  0.75443715373377 0.62073051164566\n" 
      "11.686206559208  0.62073051164566 0.58423274700635";
    A.Print("A:\n");
    Pds::Matrix D;
    Pds::Matrix V;
    
    D=A.EigenValues();
    D.Print("D:\n");
    
    V=A.EigenVectors(D);
    V.Print("V:\n");
    
    return 0;
}