Path Tracer
|
A bi conjugate gradient stabilized solver for sparse square problems. More...
#include <BiCGSTAB.h>
Public Types | |
typedef _MatrixType | MatrixType |
typedef MatrixType::Scalar | Scalar |
typedef MatrixType::RealScalar | RealScalar |
typedef _Preconditioner | Preconditioner |
Public Member Functions | |
BiCGSTAB () | |
template<typename MatrixDerived > | |
BiCGSTAB (const EigenBase< MatrixDerived > &A) | |
template<typename Rhs , typename Dest > | |
void | _solve_vector_with_guess_impl (const Rhs &b, Dest &x) const |
A bi conjugate gradient stabilized solver for sparse square problems.
This class allows to solve for A.x = b sparse linear problems using a bi conjugate gradient stabilized algorithm. The vectors x and b can be either dense or sparse.
_MatrixType | the type of the sparse matrix A, can be a dense or a sparse matrix. |
_Preconditioner | the type of the preconditioner. Default is DiagonalPreconditioner |
\implsparsesolverconcept
The maximal number of iterations and tolerance value can be controlled via the setMaxIterations() and setTolerance() methods. The defaults are the size of the problem for the maximal number of iterations and NumTraits<Scalar>::epsilon() for the tolerance.
The tolerance corresponds to the relative residual error: |Ax-b|/|b|
Performance: when using sparse matrices, best performance is achied for a row-major sparse matrix format. Moreover, in this case multi-threading can be exploited if the user code is compiled with OpenMP enabled. See TopicMultiThreading for details.
This class can be used as the direct solver classes. Here is a typical usage example:
By default the iterations start with x=0 as an initial guess of the solution. One can control the start using the solveWithGuess() method.
BiCGSTAB can also be used in a matrix-free context, see the following example .
|
inline |
Default constructor.
|
inlineexplicit |
Initialize the solver with matrix A for further Ax=b
solving.
This constructor is a shortcut for the default constructor followed by a call to compute().