239     Index findSmallSubdiagEntry(Index iu);
240     void splitOffTwoRows(Index iu, bool computeU, const Scalar& exshift);
241     void computeShift(Index iu, Index iter, Scalar& exshift, Vector3s& shiftInfo);
242 …void initFrancisQRStep(Index il, Index iu, const Vector3s& shiftInfo, Index& im, Vector3s& firstHo…
243 …void performFrancisQRStep(Index il, Index im, Index iu, bool computeU, const Vector3s& firstHouseh…
300   Index iu = m_matT.cols() - 1;  in computeFromHessenberg()  local
308     while (iu >= 0)  in computeFromHessenberg()
310       Index il = findSmallSubdiagEntry(iu);  in computeFromHessenberg()
313       if (il == iu) // One root found  in computeFromHessenberg()
315         m_matT.coeffRef(iu,iu) = m_matT.coeff(iu,iu) + exshift;  in computeFromHessenberg()
316         if (iu > 0)  in computeFromHessenberg()
317           m_matT.coeffRef(iu, iu-1) = Scalar(0);  in computeFromHessenberg()
318         iu--;  in computeFromHessenberg()
321       else if (il == iu-1) // Two roots found  in computeFromHessenberg()
323         splitOffTwoRows(iu, computeU, exshift);  in computeFromHessenberg()
324         iu -= 2;  in computeFromHessenberg()
331         computeShift(iu, iter, exshift, shiftInfo);  in computeFromHessenberg()
336         initFrancisQRStep(il, iu, shiftInfo, im, firstHouseholderVector);  in computeFromHessenberg()
337         performFrancisQRStep(il, im, iu, computeU, firstHouseholderVector, workspace);  in computeFromHessenberg()
367 inline Index RealSchur<MatrixType>::findSmallSubdiagEntry(Index iu)  in findSmallSubdiagEntry()  argument
370   Index res = iu;  in findSmallSubdiagEntry()
383 inline void RealSchur<MatrixType>::splitOffTwoRows(Index iu, bool computeU, const Scalar& exshift)  in splitOffTwoRows()  argument
391   Scalar p = Scalar(0.5) * (m_matT.coeff(iu-1,iu-1) - m_matT.coeff(iu,iu));  in splitOffTwoRows()
392 …Scalar q = p * p + m_matT.coeff(iu,iu-1) * m_matT.coeff(iu-1,iu);   // q = tr^2 / 4 - det = discr/4  in splitOffTwoRows()
393   m_matT.coeffRef(iu,iu) += exshift;  in splitOffTwoRows()
394   m_matT.coeffRef(iu-1,iu-1) += exshift;  in splitOffTwoRows()
401       rot.makeGivens(p + z, m_matT.coeff(iu, iu-1));  in splitOffTwoRows()
403       rot.makeGivens(p - z, m_matT.coeff(iu, iu-1));  in splitOffTwoRows()
405     m_matT.rightCols(size-iu+1).applyOnTheLeft(iu-1, iu, rot.adjoint());  in splitOffTwoRows()
406     m_matT.topRows(iu+1).applyOnTheRight(iu-1, iu, rot);  in splitOffTwoRows()
407     m_matT.coeffRef(iu, iu-1) = Scalar(0);   in splitOffTwoRows()
409       m_matU.applyOnTheRight(iu-1, iu, rot);  in splitOffTwoRows()
412   if (iu > 1)   in splitOffTwoRows()
413     m_matT.coeffRef(iu-1, iu-2) = Scalar(0);  in splitOffTwoRows()
418 inline void RealSchur<MatrixType>::computeShift(Index iu, Index iter, Scalar& exshift, Vector3s& sh…  in computeShift()  argument
422   shiftInfo.coeffRef(0) = m_matT.coeff(iu,iu);  in computeShift()
423   shiftInfo.coeffRef(1) = m_matT.coeff(iu-1,iu-1);  in computeShift()
424   shiftInfo.coeffRef(2) = m_matT.coeff(iu,iu-1) * m_matT.coeff(iu-1,iu);  in computeShift()
430     for (Index i = 0; i <= iu; ++i)  in computeShift()
432     Scalar s = abs(m_matT.coeff(iu,iu-1)) + abs(m_matT.coeff(iu-1,iu-2));  in computeShift()
451       for (Index i = 0; i <= iu; ++i)  in computeShift()
460 inline void RealSchur<MatrixType>::initFrancisQRStep(Index il, Index iu, const Vector3s& shiftInfo,…  in initFrancisQRStep()  argument
465   for (im = iu-2; im >= il; --im)  in initFrancisQRStep()
485 inline void RealSchur<MatrixType>::performFrancisQRStep(Index il, Index im, Index iu, bool computeU…  in performFrancisQRStep()  argument
488   eigen_assert(im <= iu-2);  in performFrancisQRStep()
492   for (Index k = im; k <= iu-2; ++k)  in performFrancisQRStep()
515       m_matT.block(0, k, (std::min)(iu,k+3) + 1, 3).applyHouseholderOnTheRight(ess, tau, workspace);  in performFrancisQRStep()
521   Matrix<Scalar, 2, 1> v = m_matT.template block<2,1>(iu-1, iu-2);  in performFrancisQRStep()
528     m_matT.coeffRef(iu-1, iu-2) = beta;  in performFrancisQRStep()
529     m_matT.block(iu-1, iu-1, 2, size-iu+1).applyHouseholderOnTheLeft(ess, tau, workspace);  in performFrancisQRStep()
530     m_matT.block(0, iu-1, iu+1, 2).applyHouseholderOnTheRight(ess, tau, workspace);  in performFrancisQRStep()
532       m_matU.block(0, iu-1, size, 2).applyHouseholderOnTheRight(ess, tau, workspace);  in performFrancisQRStep()
536   for (Index i = im+2; i <= iu; ++i)  in performFrancisQRStep()