Module solve 

Hermitian eigensolvers, Krylov evolution, and thermal Lanczos methods.

Structs

Eigensystem

Values, vectors, residual evidence, and work counters from an eigensolve.

EighOptions

Controls whether eigh_with_options retains the complete eigenvector matrix.

EigshOptions

Controls target selection, search-space size, and convergence for eigsh.

EigshWorkspace

Reusable state for a sequence of related Hermitian eigenproblems.

EvolutionDiagnostics

Algorithmic work performed by Hermitian Krylov time evolution.

EvolutionOptions

Time grid and adaptive Krylov controls for state evolution.

ExpmActionPlan

Prepared Al-Mohy–Higham exponential-action plan.

ExpmMultiplyParallel

Reusable exponential-action plan for vectors and batches.

LanczosDecomposition

Complete orthonormal basis and real symmetric tridiagonal projection.

LanczosIter

Iterator that streams a fully reorthogonalized Lanczos recurrence.

LanczosOptions

Dimension and breakdown tolerance for a Lanczos decomposition.

LanczosRitzDecomposition

LanczosVector

One streamed vector and neighboring coefficients of a Lanczos recurrence.

ProjectedThermalObservable

Observable data after projecting the language- or backend-owned action into a Lanczos basis.

RhsEvolutionOptions

Time grid and explicit-step controls for a caller-defined right-hand side.

ShiftInvertPlan

Reusable action of (A - shift I)^{-1}. Stored CSC operators cache one sparse factorization; other operators reuse the plan and solve with restarted GMRES without materializing A.

StateBatchTrajectory

Column-oriented batch trajectory: states[time_index][column_index].

StateTrajectory

State vectors sampled at the requested physical times.

ThermalIteration

ThermalObservableIteration

Enums

SpectrumTarget

Spectral region requested from a selected Hermitian eigensolver.

ThermalLanczosMethod

Finite-temperature contraction applied to a precomputed Lanczos eigensystem and observable projections.

Functions

eigh

Complete eigendecomposition of a finite Hermitian operator.

eigh_with_options

Compute the complete Hermitian spectrum with optional vector elision.

eigsh

Selected Hermitian eigenpairs.

eigsh_values

Return only selected eigenvalues while using the same convergence checks as eigsh.

eigsh_with_initial

Compute selected eigenpairs from one explicit initial vector.

eigsh_with_initial_subspace

Solve from a complete user-supplied initial subspace.

eigsh_with_workspace

Solve one member of a related operator family and update its reusable invariant-subspace workspace.

evolve

Time evolution on an arbitrary square stored or matrix-free operator.

evolve_batch

Evolve independent column states without changing their column ordering.

evolve_density

Liouville-von Neumann evolution of a row-major density matrix under a Hermitian static Hamiltonian.

evolve_rhs

Integrate an arbitrary complex right-hand side dstate/dt = f(t, state).

evolve_time_dependent

Adaptive fourth-order evolution for an explicitly time-dependent operator.

evolve_time_dependent_batch

Batched counterpart of evolve_time_dependent.

evolve_time_dependent_batch_from

Batched counterpart of evolve_time_dependent_from.

evolve_time_dependent_from

Evolve an explicitly time-dependent operator from an arbitrary absolute start time.

evolve_with_diagnostics

Time evolution on an arbitrary square stored or matrix-free operator.

expm_lanczos

expm_multiply

Exponential action over a time grid. Hermitian Hamiltonians reuse each residual-controlled Lanczos projection across the longest accepted prefix.

ftlm_observable_iteration

QuSpin-compatible one-sided FTLM observable estimates.

ftlm_static_iteration

One finite-temperature Lanczos random-vector iteration.

lanczos_full

Materialize the full Lanczos basis and tridiagonal coefficients.

lanczos_iter

Start a validated streaming Lanczos decomposition.

lanczos_ritz

Full Lanczos basis plus the sorted eigensystem of its tridiagonal projection. This is the reusable native object behind compatibility interfaces which expose both Ritz data and later reconstruction.

linear_combination_qt

ltlm_observable_iteration

Symmetric low-temperature Lanczos observable estimates.

ltlm_static_iteration

Low-temperature Lanczos iteration using a ground-energy shifted Boltzmann evaluation for numerical stability.

thermal_observable_contraction

Contract projected observables with an existing Lanczos Ritz eigensystem.