diff options
Diffstat (limited to 'Eigen/src/Core/Dot.h')
| -rw-r--r-- | Eigen/src/Core/Dot.h | 125 |
1 files changed, 0 insertions, 125 deletions
diff --git a/Eigen/src/Core/Dot.h b/Eigen/src/Core/Dot.h index d97f5837f..9e84d72bb 100644 --- a/Eigen/src/Core/Dot.h +++ b/Eigen/src/Core/Dot.h @@ -292,131 +292,6 @@ inline typename NumTraits<typename ei_traits<Derived>::Scalar>::Real MatrixBase< return ei_sqrt(squaredNorm()); } -/** \returns the \em l2 norm of \c *this using a numerically more stable - * algorithm. - * - * \sa norm(), dot(), squaredNorm(), blueNorm() - */ -template<typename Derived> -inline typename NumTraits<typename ei_traits<Derived>::Scalar>::Real -MatrixBase<Derived>::stableNorm() const -{ - return this->cwise().abs().redux(ei_scalar_hypot_op<RealScalar>()); -} - -/** \returns the \em l2 norm of \c *this using the Blue's algorithm. - * A Portable Fortran Program to Find the Euclidean Norm of a Vector, - * ACM TOMS, Vol 4, Issue 1, 1978. - * - * \sa norm(), dot(), squaredNorm(), stableNorm() - */ -template<typename Derived> -inline typename NumTraits<typename ei_traits<Derived>::Scalar>::Real -MatrixBase<Derived>::blueNorm() const -{ - static int nmax = -1; - static Scalar b1, b2, s1m, s2m, overfl, rbig, relerr; - int n; - Scalar ax, abig, amed, asml; - - if(nmax <= 0) - { - int nbig, ibeta, it, iemin, iemax, iexp; - Scalar abig, eps; - // This program calculates the machine-dependent constants - // bl, b2, slm, s2m, relerr overfl, nmax - // from the "basic" machine-dependent numbers - // nbig, ibeta, it, iemin, iemax, rbig. - // The following define the basic machine-dependent constants. - // For portability, the PORT subprograms "ilmaeh" and "rlmach" - // are used. For any specific computer, each of the assignment - // statements can be replaced - nbig = std::numeric_limits<int>::max(); // largest integer - ibeta = std::numeric_limits<Scalar>::radix; //NumTraits<Scalar>::Base; // base for floating-point numbers - it = std::numeric_limits<Scalar>::digits; //NumTraits<Scalar>::Mantissa; // number of base-beta digits in mantissa - iemin = std::numeric_limits<Scalar>::min_exponent; // minimum exponent - iemax = std::numeric_limits<Scalar>::max_exponent; // maximum exponent - rbig = std::numeric_limits<Scalar>::max(); // largest floating-point number - - // Check the basic machine-dependent constants. - if(iemin > 1 - 2*it || 1+it>iemax || (it==2 && ibeta<5) - || (it<=4 && ibeta <= 3 ) || it<2) - { - ei_assert(false && "the algorithm cannot be guaranteed on this computer"); - } - iexp = -((1-iemin)/2); - b1 = std::pow(ibeta, iexp); // lower boundary of midrange - iexp = (iemax + 1 - it)/2; - b2 = std::pow(ibeta,iexp); // upper boundary of midrange - - iexp = (2-iemin)/2; - s1m = std::pow(ibeta,iexp); // scaling factor for lower range - iexp = - ((iemax+it)/2); - s2m = std::pow(ibeta,iexp); // scaling factor for upper range - - overfl = rbig*s2m; // overfow boundary for abig - eps = std::pow(ibeta, 1-it); - relerr = ei_sqrt(eps); // tolerance for neglecting asml - abig = 1.0/eps - 1.0; - if (Scalar(nbig)>abig) nmax = abig; // largest safe n - else nmax = nbig; - } - n = size(); - if(n==0) - return 0; - asml = Scalar(0); - amed = Scalar(0); - abig = Scalar(0); - for(int j=0; j<n; ++j) - { - ax = ei_abs(coeff(j)); - if(ax > b2) abig += ei_abs2(ax*s2m); - else if(ax < b1) asml += ei_abs2(ax*s1m); - else amed += ei_abs2(ax); - } - if(abig > Scalar(0)) - { - abig = ei_sqrt(abig); - if(abig > overfl) - { - ei_assert(false && "overflow"); - return rbig; - } - if(amed > Scalar(0)) - { - abig = abig/s2m; - amed = ei_sqrt(amed); - } - else - { - return abig/s2m; - } - - } - else if(asml > Scalar(0)) - { - if (amed > Scalar(0)) - { - abig = ei_sqrt(amed); - amed = ei_sqrt(asml) / s1m; - } - else - { - return ei_sqrt(asml)/s1m; - } - } - else - { - return ei_sqrt(amed); - } - asml = std::min(abig, amed); - abig = std::max(abig, amed); - if(asml <= abig*relerr) - return abig; - else - return abig * ei_sqrt(Scalar(1) + ei_abs2(asml/abig)); -} - /** \returns an expression of the quotient of *this by its own norm. * * \only_for_vectors |