Function rmatrixbdunpackq

src/ortfac.cpp:1565–1605

Unpacking matrix Q which reduces a matrix to bidiagonal form. Input parameters: QP - matrices Q and P in compact form. Output of ToBidiagonal subroutine. M - number of rows in matrix A. N - number of columns in matrix A. TAUQ - scalar factors which are used to form Q. Output of ToBidiagonal subrout

     Bochkanov Sergey
*************************************************************************/
void rmatrixbdunpackq(const ap::real_2d_array& qp,
     int m,
     int n,
     const ap::real_1d_array& tauq,
     int qcolumns,
     ap::real_2d_array& q)
{
    int i;
    int j;

    ap::ap_error::make_assertion(qcolumns<=m, "RMatrixBDUnpackQ: QColumns>M!");
    ap::ap_error::make_assertion(qcolumns>=0, "RMatrixBDUnpackQ: QColumns<0!");
    if( m==0||n==0||qcolumns==0 )
    {
        return;
    }
    
    //
    // prepare Q
    //
    q.setlength(m, qcolumns);
    for(i = 0; i <= m-1; i++)
    {
        for(j = 0; j <= qcolumns-1; j++)
        {
            if( i==j )
            {
                q(i,j) = 1;
            }
            else
            {
                q(i,j) = 0;
            }
        }
    }
    
    //
    // Calculate
    //
    rmatrixbdmultiplybyq(qp, m, n, tauq, q, m, qcolumns, false, false);
}


/*************************************************************************