/**
* An orthogonal matrix that has the following property: H = Q<sup>T</sup>AQ
*
* @param Q If not null then the results will be stored here. Otherwise a new matrix will be created.
* @return The extracted Q matrix.
*/
public DMatrixRMaj getQ(DMatrixRMaj Q)
{
Q = UtilDecompositons_DDRM.checkIdentity(Q, N, N);
for (int j = N - 2; j >= 0; j--)
{
u[j + 1] = 1;
for (int i = j + 2; i < N; i++)
{
u[i] = QH.get(i, j);
}
QrHelperFunctions_DDRM.rank1UpdateMultR(Q, u, gammas[j], j + 1, j + 1, N, b);
}
return(Q);
}
/**
* An orthogonal matrix that has the following property: T = Q<sup>T</sup>AQ
*
* @param Q If not null then the results will be stored here. Otherwise a new matrix will be created.
* @return The extracted Q matrix.
*/
public DMatrixRMaj getQ(DMatrixRMaj Q)
{
Q = UtilDecompositons_DDRM.checkIdentity(Q, N, N);
for (int i = 0; i < N; i++)
{
w[i] = 0;
}
for (int j = N - 2; j >= 0; j--)
{
w[j + 1] = 1;
for (int i = j + 2; i < N; i++)
{
w[i] = QT.get(j, i);
}
QrHelperFunctions_DDRM.rank1UpdateMultR(Q, w, gammas[j + 1], j + 1, j + 1, N, b);
// Q.print();
}
return(Q);
}
/**
* Computes the Q matrix from the imformation stored in the QR matrix. This
* operation requires about 4(m<sup>2</sup>n-mn<sup>2</sup>+n<sup>3</sup>/3) flops.
*
* @param Q The orthogonal Q matrix.
*/
public virtual DMatrixRMaj getQ(DMatrixRMaj Q, bool compact)
{
if (compact)
{
Q = UtilDecompositons_DDRM.checkIdentity(Q, numRows, minLength);
}
else
{
Q = UtilDecompositons_DDRM.checkIdentity(Q, numRows, numRows);
}
for (int j = minLength - 1; j >= 0; j--)
{
double[] u = dataQR[j];
double vv = u[j];
u[j] = 1;
QrHelperFunctions_DDRM.rank1UpdateMultR(Q, u, gammas[j], j, j, numRows, v);
u[j] = vv;
}
return(Q);
}
/**
* An orthogonal matrix that has the following property: T = Q<sup>T</sup>AQ
*
* @param Q If not null then the results will be stored here. Otherwise a new matrix will be created.
* @return The extracted Q matrix.
*/
//@Override
public DMatrixRMaj getQ(DMatrixRMaj Q, bool transposed)
{
Q = UtilDecompositons_DDRM.checkIdentity(Q, N, N);
for (int i = 0; i < N; i++)
{
w[i] = 0;
}
if (transposed)
{
for (int j = N - 2; j >= 0; j--)
{
w[j + 1] = 1;
for (int i = j + 2; i < N; i++)
{
w[i] = QT.data[j * N + i];
}
QrHelperFunctions_DDRM.rank1UpdateMultL(Q, w, gammas[j + 1], j + 1, j + 1, N);
}
}
else
{
for (int j = N - 2; j >= 0; j--)
{
w[j + 1] = 1;
for (int i = j + 2; i < N; i++)
{
w[i] = QT.get(j, i);
}
QrHelperFunctions_DDRM.rank1UpdateMultR(Q, w, gammas[j + 1], j + 1, j + 1, N, b);
}
}
return(Q);
}