11#ifndef EIGEN_HOUSEHOLDER_H
12#define EIGEN_HOUSEHOLDER_H
14#include "./InternalHeaderCheck.h"
19template<
int n>
struct decrement_size
43template<
typename Derived>
48 makeHouseholder(essentialPart, tau, beta);
66template<
typename Derived>
67template<
typename EssentialPart>
70 EssentialPart& essential,
72 RealScalar& beta)
const
77 EIGEN_STATIC_ASSERT_VECTOR_ONLY(EssentialPart)
80 RealScalar tailSqNorm = size()==1 ? RealScalar(0) : tail.squaredNorm();
82 const RealScalar tol = (std::numeric_limits<RealScalar>::min)();
84 if(tailSqNorm <= tol && numext::abs2(numext::imag(c0))<=tol)
87 beta = numext::real(c0);
92 beta =
sqrt(numext::abs2(c0) + tailSqNorm);
93 if (numext::real(c0)>=RealScalar(0))
95 essential = tail / (c0 - beta);
96 tau =
conj((beta - c0) / beta);
115template<
typename Derived>
116template<
typename EssentialPart>
119 const EssentialPart& essential,
131 tmp.noalias() = essential.adjoint() * bottom;
133 this->row(0) -= tau * tmp;
134 bottom.noalias() -= tau * essential * tmp;
153template<
typename Derived>
154template<
typename EssentialPart>
157 const EssentialPart& essential,
169 tmp.noalias() = right * essential;
171 this->col(0) -= tau * tmp;
172 right.noalias() -= tau * tmp * essential.adjoint();
Expression of a fixed-size or dynamic-size block.
Definition: Block.h:107
internal::traits< Derived >::Scalar Scalar
Definition: DenseBase.h:61
A matrix or vector expression mapping an existing array of data.
Definition: Map.h:98
void makeHouseholder(EssentialPart &essential, Scalar &tau, RealScalar &beta) const
Definition: Householder.h:69
void applyHouseholderOnTheLeft(const EssentialPart &essential, const Scalar &tau, Scalar *workspace)
Definition: Householder.h:118
void applyHouseholderOnTheRight(const EssentialPart &essential, const Scalar &tau, Scalar *workspace)
Definition: Householder.h:156
void makeHouseholderInPlace(Scalar &tau, RealScalar &beta)
Definition: Householder.h:45
Expression of a fixed-size or dynamic-size sub-vector.
Definition: VectorBlock.h:62
Namespace containing all symbols from the Eigen library.
Definition: B01_Experimental.dox:1
const Eigen::CwiseUnaryOp< Eigen::internal::scalar_sqrt_op< typename Derived::Scalar >, const Derived > sqrt(const Eigen::ArrayBase< Derived > &x)
const Eigen::CwiseUnaryOp< Eigen::internal::scalar_conjugate_op< typename Derived::Scalar >, const Derived > conj(const Eigen::ArrayBase< Derived > &x)
const int Dynamic
Definition: Constants.h:24