10#ifndef EIGEN_BASIC_PRECONDITIONERS_H
11#define EIGEN_BASIC_PRECONDITIONERS_H
35template <
typename _Scalar>
38 typedef _Scalar Scalar;
41 typedef typename Vector::StorageIndex StorageIndex;
49 template<
typename MatType>
55 EIGEN_CONSTEXPR
Index rows()
const EIGEN_NOEXCEPT {
return m_invdiag.size(); }
56 EIGEN_CONSTEXPR
Index cols()
const EIGEN_NOEXCEPT {
return m_invdiag.size(); }
58 template<
typename MatType>
64 template<
typename MatType>
67 m_invdiag.
resize(mat.cols());
68 for(
int j=0; j<mat.outerSize(); ++j)
70 typename MatType::InnerIterator it(mat,j);
71 while(it && it.index()!=j) ++it;
72 if(it && it.index()==j && it.value()!=Scalar(0))
73 m_invdiag(j) = Scalar(1)/it.value();
75 m_invdiag(j) = Scalar(1);
77 m_isInitialized =
true;
81 template<
typename MatType>
84 return factorize(mat);
88 template<
typename Rhs,
typename Dest>
89 void _solve_impl(
const Rhs& b, Dest& x)
const
91 x = m_invdiag.array() * b.array() ;
97 eigen_assert(m_isInitialized &&
"DiagonalPreconditioner is not initialized.");
98 eigen_assert(m_invdiag.size()==b.
rows()
99 &&
"DiagonalPreconditioner::solve(): invalid number of rows of the right hand side matrix b");
107 bool m_isInitialized;
127template <
typename _Scalar>
130 typedef _Scalar Scalar;
131 typedef typename NumTraits<Scalar>::Real RealScalar;
133 using Base::m_invdiag;
138 template<
typename MatType>
144 template<
typename MatType>
150 template<
typename MatType>
154 m_invdiag.
resize(mat.cols());
155 if(MatType::IsRowMajor)
158 for(
Index j=0; j<mat.outerSize(); ++j)
160 for(
typename MatType::InnerIterator it(mat,j); it; ++it)
161 m_invdiag(it.index()) += numext::abs2(it.value());
163 for(
Index j=0; j<mat.cols(); ++j)
164 if(numext::real(m_invdiag(j))>RealScalar(0))
165 m_invdiag(j) = RealScalar(1)/numext::real(m_invdiag(j));
169 for(
Index j=0; j<mat.outerSize(); ++j)
171 RealScalar sum = mat.col(j).squaredNorm();
172 if(sum>RealScalar(0))
173 m_invdiag(j) = RealScalar(1)/sum;
175 m_invdiag(j) = RealScalar(1);
178 Base::m_isInitialized =
true;
182 template<
typename MatType>
185 return factorize(mat);
206 template<
typename MatrixType>
209 template<
typename MatrixType>
212 template<
typename MatrixType>
215 template<
typename MatrixType>
218 template<
typename Rhs>
219 inline const Rhs& solve(
const Rhs& b)
const {
return b; }
Derived & derived()
Definition: EigenBase.h:46
EIGEN_CONSTEXPR Index rows() const EIGEN_NOEXCEPT
Definition: EigenBase.h:60
A preconditioner based on the digonal entries.
Definition: BasicPreconditioners.h:37
A naive preconditioner which approximates any matrix as the identity matrix.
Definition: BasicPreconditioners.h:201
Jacobi preconditioner for LeastSquaresConjugateGradient.
Definition: BasicPreconditioners.h:129
Base class for all dense matrices, vectors, and expressions.
Definition: MatrixBase.h:50
The matrix class, also used for vectors and row-vectors.
Definition: Matrix.h:180
void resize(Index rows, Index cols)
Definition: PlainObjectBase.h:271
Derived & setZero(Index size)
Definition: CwiseNullaryOp.h:562
Pseudo expression representing a solving operation.
Definition: Solve.h:63
ComputationInfo
Definition: Constants.h:440
@ Success
Definition: Constants.h:442
Namespace containing all symbols from the Eigen library.
Definition: Core:141
EIGEN_DEFAULT_DENSE_INDEX_TYPE Index
The Index type as used for the API.
Definition: Meta.h:74
const int Dynamic
Definition: Constants.h:22