ffsim.linalg

Linear algebra utilities

GivensRotation(c, s, i, j)	A Givens rotation.
apply_matrix_to_slices(target, mat, slices, *)	Apply a matrix to slices of a target tensor.
double_factorized(two_body_tensor, *[, tol, ...])	Double-factorized decomposition of a two-body tensor.
double_factorized_t2(t2_amplitudes, *[, ...])	Double-factorized decomposition of \(t_2\) amplitudes.
double_factorized_t2_alpha_beta(t2_amplitudes, *)	Double-factorized decomposition of alpha-beta \(t_2\) amplitudes.
expm_multiply_taylor(mat, vec[, tol])	Compute expm(mat) @ vec using a Taylor series expansion.
givens_decomposition(mat)	Givens rotation decomposition of a unitary matrix.
is_antihermitian(mat, *[, rtol, atol])	Determine if a matrix is approximately anti-Hermitian.
is_hermitian(mat, *[, rtol, atol])	Determine if a matrix is approximately Hermitian.
is_orthogonal(mat, *[, rtol, atol])	Determine if a matrix is approximately orthogonal.
is_real_symmetric(mat, *[, rtol, atol])	Determine if a matrix is real and approximately symmetric.
is_special_orthogonal(mat, *[, rtol, atol])	Determine if a matrix is approximately special orthogonal.
is_unitary(mat, *[, rtol, atol])	Determine if a matrix is approximately unitary.
lup(mat)	Column-pivoted LU decomposition of a matrix.
match_global_phase(a, b)	Phase the given arrays so that their phases match at one entry.
modified_cholesky(mat, *[, tol, max_vecs])	Modified Cholesky decomposition.
one_hot(shape, index, *[, dtype])	Return an array of all zeros except for a one at a specified index.
reduced_matrix(mat, vecs)	Compute reduced matrix within a subspace spanned by some vectors.