qttools.greens_function_solver.rgf_dist#

Classes

source class RGFDist(max_batch_size: int = 100)

Distributed selected inversion solver.

Initializes the selected inversion solver.

Parameters

solve_lesser : bool, optional — Whether to solve the quadratic system associated with the lesser right-hand-side, by default False.
solve_greater : bool, optional — Whether to solve the quadratic system associated with the greater right-hand-side, by default False.
max_batch_size : int, optional — Maximum batch size to use when inverting the matrix, by default 100.

Methods

Performs selected inversion of a block-tridiagonal matrix.

Parameters

Returns

None | DSDBSparse — If out is None, returns None. Otherwise, returns the inverted matrix as a DSDBSparse object.

source method RGFDist.selected_solve(a: DSDBSparse, sigma_lesser: DSDBSparse, sigma_greater: DSDBSparse, out: tuple[DSDBSparse, ...], obc_blocks: OBCBlocks | None = None, return_retarded: bool = False)

Performs selected inversion of a block-tridiagonal matrix.

Can optionally solve the quadratic system associated with the Bl and Bg matrices in the equation AXA^T = B.

Parameters

a : DSDBSparse — Matrix to invert.
sigma_lesser : DSDBSparse — Lesser matrix. This matrix is expected to be skew-hermitian, i.e. \(\Sigma_{ij} = -\Sigma_{ji}^*\).
sigma_greater : DSDBSparse — Greater matrix. This matrix is expected to be skew-hermitian, i.e. \(\Sigma_{ij} = -\Sigma_{ji}^*\).
out : tuple[DSDBSparse, ...] — Preallocated output matrices, by default None
obc_blocks : OBCBlocks, optional — OBC blocks for lesser, greater and retarded Green's functions. By default None.
return_retarded : bool, optional — Wether the retarded Green's function should be returned along with lesser and greater, by default False

Raises