/*
Solve the overconstrained linear system Ma = b using a least
squares error (pseudo inverse) approach.
*/
int solve_system (dmat M, dmat a, dmat b)
/*
int solve_system (M, a, b)
dmat M,
a,
b;
*/
{
dmat Mt,MtM,Mdag;
int error;
if ((M.ub1 - M.lb1) < (M.ub2 - M.lb2))
{
fprintf (stderr, "solve_system: matrix M has more columns than rows\n");
return (-1);
}
Mt = newdmat (M.lb2, M.ub2, M.lb1, M.ub1, &error);
if (error)
{ fprintf (stderr, "solve_system: unable to allocate matrix M_transpose\n"); return (-1); }
if (transpose (M, Mt)!=0)
{ fprintf (stderr, "solve_system: unable to transpose matrix M\n"); return (-1); }
MtM = newdmat (M.lb2, M.ub2, M.lb2, M.ub2, &error);
if (error)
{ fprintf (stderr, "solve_system: unable to allocate matrix M_transpose_M\n"); return (-1); }
if (matmul (Mt, M, MtM)!=0)
{ fprintf (stderr, "solve_system: unable to compute matrix product of M_transpose and M\n"); return (-1); }
if (fabs (matinvert (MtM)) < 0.001)
{
fprintf (stderr, "solve_system: determinant of matrix M_transpose_M is too small\n");
return (-1);
}
/*
if (errno) {
fprintf (stderr, "solve_system: error during matrix inversion\n");
return (-1);
}
*/
Mdag = newdmat (M.lb2, M.ub2, M.lb1, M.ub1, &error);
if (error)
{ fprintf (stderr, "solve_system: unable to allocate matrix M_diag\n"); return (-1); }
if (matmul (MtM, Mt, Mdag)!=0)
{
fprintf (stderr, "solve_system: unable to compute matrix product of M_transpose_M and M_transpose\n");
return (-1);
}
if (matmul (Mdag, b, a)!=0)
{
fprintf (stderr, "solve_system: unable to compute matrix product of M_diag and b\n");
return (-1);
}
freemat (Mt); freemat (MtM); freemat (Mdag);
return 0;
}
/*
Solve the overconstrained linear system Ma = b using a least
squares error (pseudo inverse) approach.
*/
int solve_system (dmat M, dmat a,dmat b)
{
dmat Mt,
MtM,
Mdag;
//AfxMessageBox("S1");
if ((M.ub1 - M.lb1) < (M.ub2 - M.lb2)) {
fprintf (stderr, "solve_system: matrix M has more columns than rows\n");
return (-1);
}
//AfxMessageBox("S2");
Mt = newdmat (M.lb2, M.ub2, M.lb1, M.ub1, &errno);
if (errno) {
fprintf (stderr, "solve_system: unable to allocate matrix M_transpose\n");
return (-2);
}
//AfxMessageBox("S3");
transpose (M, Mt);
if (errno) {
fprintf (stderr, "solve_system: unable to transpose matrix M\n");
return (-3);
}
//AfxMessageBox("S4");
MtM = newdmat (M.lb2, M.ub2, M.lb2, M.ub2, &errno);
if (errno) {
fprintf (stderr, "solve_system: unable to allocate matrix M_transpose_M\n");
return (-4);
}
//AfxMessageBox("S5");
matmul (Mt, M, MtM);
if (errno) {
fprintf (stderr, "solve_system: unable to compute matrix product of M_transpose and M\n");
return (-5);
}
//modified by Dickson
//AfxMessageBox("S6");
double aa=fabs (matinvert (MtM));
//AfxMessageBox("S7");
//if (aa < 0.001) {
//CString str;
//str.Format("determinant=%f",aa);
//AfxMessageBox("S71");
//AfxMessageBox(str);
//AfxMessageBox("S8");
if (aa < 0.001) {
fprintf (stderr, "solve_system: determinant of matrix M_transpose_M is too small\n");
return (-6);
}
if (errno) {
fprintf (stderr, "solve_system: error during matrix inversion\n");
return (-7);
}
Mdag = newdmat (M.lb2, M.ub2, M.lb1, M.ub1, &errno);
if (errno) {
fprintf (stderr, "solve_system: unable to allocate matrix M_diag\n");
return (-8);
}
matmul (MtM, Mt, Mdag);
if (errno) {
fprintf (stderr, "solve_system: unable to compute matrix product of M_transpose_M and M_transpose\n");
return (-9);
}
matmul (Mdag, b, a);
if (errno) {
fprintf (stderr, "solve_system: unable to compute matrix product of M_diag and b\n");
return (-10);
}
freemat (Mt);
freemat (MtM);
freemat (Mdag);
return 0;
}
