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Linear Algebra Utilities

This module provides various linear algebra utilities.

apply_unitary(vec, operator, norb, nelec[, copy])Applies a unitary transformation to a state vector.
givens_decomposition(unitary)Decomposes a unitary matrix into Givens rotations and diagonal phases.
givens_decomposition_slater(orbital_coeffs)Decomposes the occupied orbitals of a Slater determinant into Givens rotations.
double_factorized_2body(two_body_tensor, tol)Double-factorized decomposition of a real two-body tensor.
double_factorized_t2(t2_amplitudes, tol[, ...])Double-factorized decomposition of spin-restricted t2t_2 amplitudes.
linear_operator(operator, norb, nelec)Returns a scipy.sparse.linalg.LinearOperator for an operator on the (norb, nelec) FCI sector.
reconstruct_t2(terms, nocc)Reconstructs spin-restricted t2t_2 amplitudes from a double-factorized decomposition.
double_factorized_t2_alpha_beta(...[, max_terms])Double-factorized decomposition of alpha-beta (spin-unrestricted) t2t_2 amplitudes.
reconstruct_t2_alpha_beta(terms, norb, ...)Reconstructs alpha-beta t2t_2 amplitudes from a double-factorized decomposition.