#include <init.hpp>
Inheritance diagram for q3::PlanewaveSubspaceManager:Public Member Functions | |
| virtual | ~PlanewaveSubspaceManager ()=default |
| virtual void | apply_preconditioner (int number_of_bands, int number_of_plane_waves, const Real *kinetic_energy_squared, const Real *eigenvalues, const std::vector< bool > &band_converged, Complex *residual_wavefunctions)=0 |
| virtual int | build_correction_vectors (int basis_size, int number_of_plane_waves, int number_of_bands, int maximum_candidates, bool is_gamma_only, const Complex *eigenvector_matrix, int eigenvector_leading_dimension, const Real *eigenvalues, const std::vector< bool > &band_converged, const Real *kinetic_energy_squared, const Complex *hamiltonian_basis_vectors, const Complex *overlap_basis_vectors, Complex *correction_columns)=0 |
| virtual int | collapse_subspace (int basis_size, int number_of_plane_waves, int number_of_bands, int maximum_basis_size, bool is_gamma_only, bool is_identity_overlap, const OverlapOperator *overlap_operator, const Complex *subspace_hamiltonian, const Complex *subspace_overlap, Complex *basis_vectors, Complex *hamiltonian_basis_vectors, Complex *overlap_basis_vectors, Complex *rotation_scratch)=0 |
| virtual int | diagonalize_subspace (int basis_size, int maximum_basis_size, bool is_gamma_only, const Complex *subspace_hamiltonian, const Complex *subspace_overlap, Real *eigenvalues, Complex *eigenvector_matrix)=0 |
| virtual void | extract_eigenvectors (int basis_size, int number_of_plane_waves, int number_of_bands, int kpoint_index_state, bool is_gamma_only, const Complex *eigenvector_matrix, const Complex *basis_vectors, const Real *eigenvalues, Complex *rotated_scratch, PlanewaveKohnShamQuantumSystem &quantum_system)=0 |
| virtual int | orthogonalize_batch (int starting_vector_index, int number_of_candidates, int number_of_plane_waves, bool is_gamma_only, const OverlapOperator *overlap_operator, Complex *basis_vectors, Complex *overlap_basis_vectors)=0 |
| virtual void | set_gamma_origin_is_local (bool origin_is_local)=0 |
| virtual void | update_subspace_matrices (int start_column, int new_columns, int total_basis_size, int maximum_basis_size, int number_of_plane_waves, bool is_gamma_only, const Complex *basis_vectors, const Complex *hamiltonian_basis_vectors, const Complex *overlap_basis_vectors, Complex *subspace_hamiltonian, Complex *subspace_overlap)=0 |
|
virtualdefault |
|
pure virtual |
Apply Davidson preconditioner to residual wavefunctions.
Implemented in q3::GPUPlanewaveSubspaceManager, and q3::SerialPlanewaveSubspaceManager.
|
pure virtual |
Compute residual vectors: R = Hψ - εSψ. Build preconditioned correction vectors straight into the free columns of the basis, and return how many were written.
R_n = (HV)c_n - eps_n (SV)c_n, formed by two GEMMs whose destination is the basis itself. Nothing else is materialised: no Ritz vectors, no H|Ritz>, no separate residual array. That is the layout Quantum ESPRESSO's Davidson uses, and it is three arrays of number_of_bands x number_of_plane_waves that Q3 no longer has to hold.
Only unconverged bands contribute, and they are compacted into consecutive columns as they are written, so the caller can hand the block straight to orthogonalize_batch.
Implemented in q3::GPUPlanewaveSubspaceManager, and q3::SerialPlanewaveSubspaceManager.
|
pure virtual |
Collapse the subspace back to number_of_bands vectors by rotating the basis with the eigenvector matrix.
The rotation needs somewhere to build its result before overwriting the array it is reading, and the caller supplies one buffer of at least number_of_bands * number_of_plane_waves. One is enough because each rotation reads a different array than it writes. These used to be three members sized by maximum_basis_size, which made the collapse as expensive in memory as the basis it collapses.
The rotation matrix is the eigenvector matrix of the current subspace, and the caller already holds that subspace: subspace_hamiltonian and subspace_overlap are the incrementally updated matrices with leading dimension maximum_basis_size, complete through basis_size. Diagonalising them costs basis_size cubed; rebuilding them from the vectors first – which is what this used to do – costs two products of basis_size squared by number_of_plane_waves on top, and was the largest single compute term of a restart. Pass nullptr for either to force that rebuild, which is also the fallback when the passed matrices cannot be diagonalised: the Davidson loop asks for a collapse precisely when its own diagonalisation of them has just failed.
Returns the new basis size (= number_of_bands).
Implemented in q3::GPUPlanewaveSubspaceManager, and q3::SerialPlanewaveSubspaceManager.
|
pure virtual |
Diagonalize the subspace by solving the generalized eigenvalue problem H_sub · c = ε · S_sub · c.
Returns the LAPACK info code (0 = success).
Implemented in q3::GPUPlanewaveSubspaceManager, and q3::SerialPlanewaveSubspaceManager.
|
pure virtual |
Extract converged eigenvectors from the subspace representation and store them in the quantum system.
Implemented in q3::GPUPlanewaveSubspaceManager, and q3::SerialPlanewaveSubspaceManager.
|
pure virtual |
S-orthogonalize and normalize a batch of candidate vectors against the existing basis using modified Gram-Schmidt with S inner product.
Returns the number of accepted (linearly independent) vectors.
Implemented in q3::GPUPlanewaveSubspaceManager, and q3::SerialPlanewaveSubspaceManager.
|
pure virtual |
Whether this rank's plane-wave list begins with G = 0.
Every gamma-only inner product below is 2 Re over the stored half sphere with the origin – held once, counted twice – removed, and then reduced across the ranks sharing the coefficients. Under a reciprocal-space distribution exactly one rank holds the origin, and only that rank may remove it. Replicated layouts always hold it, which is the default. Set once per k-point, before the solve.
Implemented in q3::GPUPlanewaveSubspaceManager, and q3::SerialPlanewaveSubspaceManager.
|
pure virtual |
Incrementally update the subspace matrices H_sub and S_sub with new_columns vectors starting at start_column.
Implemented in q3::GPUPlanewaveSubspaceManager, and q3::SerialPlanewaveSubspaceManager.
1.9.8 
