239     void computeShift(Index iu, Index iter, Scalar& exshift, Vector3s& shiftInfo);
240 …void initFrancisQRStep(Index il, Index iu, const Vector3s& shiftInfo, Index& im, Vector3s& firstHo…
309         Vector3s firstHouseholderVector(0,0,0), shiftInfo;  in computeFromHessenberg()
310         computeShift(iu, iter, exshift, shiftInfo);  in computeFromHessenberg()
315         initFrancisQRStep(il, iu, shiftInfo, im, firstHouseholderVector);  in computeFromHessenberg()
397 …oid RealSchur<MatrixType>::computeShift(Index iu, Index iter, Scalar& exshift, Vector3s& shiftInfo)  in computeShift()  argument
401   shiftInfo.coeffRef(0) = m_matT.coeff(iu,iu);  in computeShift()
402   shiftInfo.coeffRef(1) = m_matT.coeff(iu-1,iu-1);  in computeShift()
403   shiftInfo.coeffRef(2) = m_matT.coeff(iu,iu-1) * m_matT.coeff(iu-1,iu);  in computeShift()
408     exshift += shiftInfo.coeff(0);  in computeShift()
410       m_matT.coeffRef(i,i) -= shiftInfo.coeff(0);  in computeShift()
412     shiftInfo.coeffRef(0) = Scalar(0.75) * s;  in computeShift()
413     shiftInfo.coeffRef(1) = Scalar(0.75) * s;  in computeShift()
414     shiftInfo.coeffRef(2) = Scalar(-0.4375) * s * s;  in computeShift()
420     Scalar s = (shiftInfo.coeff(1) - shiftInfo.coeff(0)) / Scalar(2.0);  in computeShift()
421     s = s * s + shiftInfo.coeff(2);  in computeShift()
425       if (shiftInfo.coeff(1) < shiftInfo.coeff(0))  in computeShift()
427       s = s + (shiftInfo.coeff(1) - shiftInfo.coeff(0)) / Scalar(2.0);  in computeShift()
428       s = shiftInfo.coeff(0) - shiftInfo.coeff(2) / s;  in computeShift()
432       shiftInfo.setConstant(Scalar(0.964));  in computeShift()
439 inline void RealSchur<MatrixType>::initFrancisQRStep(Index il, Index iu, const Vector3s& shiftInfo,…  in initFrancisQRStep()  argument
447     const Scalar r = shiftInfo.coeff(0) - Tmm;  in initFrancisQRStep()
448     const Scalar s = shiftInfo.coeff(1) - Tmm;  in initFrancisQRStep()
449     v.coeffRef(0) = (r * s - shiftInfo.coeff(2)) / m_matT.coeff(im+1,im) + m_matT.coeff(im,im+1);  in initFrancisQRStep()