Spectra  1.0.1
Header-only C++ Library for Large Scale Eigenvalue Problems
Spectra::DenseGenRealShiftSolve< Scalar_, Flags > Class Template Reference

#include <Spectra/MatOp/DenseGenRealShiftSolve.h>

Public Types

using Scalar = Scalar_
 

Public Member Functions

template<typename Derived >
 DenseGenRealShiftSolve (const Eigen::MatrixBase< Derived > &mat)
 
Index rows () const
 
Index cols () const
 
void set_shift (const Scalar &sigma)
 
void perform_op (const Scalar *x_in, Scalar *y_out) const
 

Detailed Description

template<typename Scalar_, int Flags = Eigen::ColMajor>
class Spectra::DenseGenRealShiftSolve< Scalar_, Flags >

This class defines the shift-solve operation on a general real matrix \(A\), i.e., calculating \(y=(A-\sigma I)^{-1}x\) for any real \(\sigma\) and vector \(x\). It is mainly used in the GenEigsRealShiftSolver eigen solver.

Template Parameters
Scalar_The element type of the matrix, for example, float, double, and long double.
FlagsEither Eigen::ColMajor or Eigen::RowMajor, indicating the storage format of the input matrix.

Definition at line 29 of file DenseGenRealShiftSolve.h.

Member Typedef Documentation

◆ Scalar

template<typename Scalar_ , int Flags = Eigen::ColMajor>
using Spectra::DenseGenRealShiftSolve< Scalar_, Flags >::Scalar = Scalar_

Element type of the matrix.

Definition at line 35 of file DenseGenRealShiftSolve.h.

Constructor & Destructor Documentation

◆ DenseGenRealShiftSolve()

template<typename Scalar_ , int Flags = Eigen::ColMajor>
template<typename Derived >
Spectra::DenseGenRealShiftSolve< Scalar_, Flags >::DenseGenRealShiftSolve ( const Eigen::MatrixBase< Derived > &  mat)
inline

Constructor to create the matrix operation object.

Parameters
matAn Eigen matrix object, whose type can be Eigen::Matrix<Scalar, ...> (e.g. Eigen::MatrixXd and Eigen::MatrixXf), or its mapped version (e.g. Eigen::Map<Eigen::MatrixXd>).

Definition at line 59 of file DenseGenRealShiftSolve.h.

Member Function Documentation

◆ rows()

template<typename Scalar_ , int Flags = Eigen::ColMajor>
Index Spectra::DenseGenRealShiftSolve< Scalar_, Flags >::rows ( ) const
inline

Return the number of rows of the underlying matrix.

Definition at line 73 of file DenseGenRealShiftSolve.h.

◆ cols()

template<typename Scalar_ , int Flags = Eigen::ColMajor>
Index Spectra::DenseGenRealShiftSolve< Scalar_, Flags >::cols ( ) const
inline

Return the number of columns of the underlying matrix.

Definition at line 77 of file DenseGenRealShiftSolve.h.

◆ set_shift()

template<typename Scalar_ , int Flags = Eigen::ColMajor>
void Spectra::DenseGenRealShiftSolve< Scalar_, Flags >::set_shift ( const Scalar sigma)
inline

Set the real shift \(\sigma\).

Definition at line 82 of file DenseGenRealShiftSolve.h.

◆ perform_op()

template<typename Scalar_ , int Flags = Eigen::ColMajor>
void Spectra::DenseGenRealShiftSolve< Scalar_, Flags >::perform_op ( const Scalar x_in,
Scalar y_out 
) const
inline

Perform the shift-solve operation \(y=(A-\sigma I)^{-1}x\).

Parameters
x_inPointer to the \(x\) vector.
y_outPointer to the \(y\) vector.

Definition at line 94 of file DenseGenRealShiftSolve.h.


The documentation for this class was generated from the following file: