| |
| namespace Eigen { |
| |
| /** |
| |
| \eigenManualPage MatrixfreeSolverExample Matrix-free solvers |
| |
| Iterative solvers such as ConjugateGradient and BiCGSTAB can be used in a matrix free context. To this end, user must provide a wrapper class inheriting EigenBase<> and implementing the following methods: |
| - Index rows() and Index cols(): returns number of rows and columns respectively |
| - operator* with and Eigen dense column vector |
| - resize(rows,cols): needed for source compatibility (can stay empty) |
| |
| Eigen::internal::traits<> must also be specialized for the wrapper type. |
| |
| For efficiency purpose, one might also want to provide a custom preconditioner. Here is an example using ConjugateGradient and implementing also a custom Jacobi preconditioner: |
| \include matrixfree_cg.cpp |
| Output: \verbinclude matrixfree_cg.out |
| |
| */ |
| |
| } |
