fulqrum.core.CSRLinearOperator

class CSRLinearOperator(*args, **kwargs)

A SciPy LinearOperator wrapper for a CSR array. Allows for parallel computation of the sparse-matrix vector product needed for eigensolving.

Methods

matvec(x)

Matrix-vector multiplication.

Attributes

H	Hermitian adjoint.
T	Transpose.
memory_size	An estimate of the raw memory size of the underlying CSR array in bytes
nnz	Number of nonzero elements in the underlying CSR matrix
ndim

matvec(x)

Matrix-vector multiplication.

Applies A to x, where A is an M x N linear operator (or batch of linear operators) and x is a row vector (or batch of such vectors).

Parameters:

x ({matrix, ndarray}) –

An array with shape (..., N) representing a row vector (or batch of row vectors).

Added in version 1.18.0: A FutureWarning is emitted for column vector input of shape (N, 1), for which an array with shape (M, 1) is returned. matmat can be called instead for identical behaviour on such input.

Returns:

y – An array with shape (..., M).

Return type:

{matrix, ndarray}

Notes

This method wraps the user-specified matvec routine or overridden _matvec method to ensure that y has the correct shape and type.

property memory_size

An estimate of the raw memory size of the underlying CSR array in bytes

Returns:

Memory size in bytes

Return type:

int

property nnz

Number of nonzero elements in the underlying CSR matrix

Returns:

int