Mfr#

class cherab.inversion.Mfr(T, dmats: Collection[Collection[spmatrix | sparray]], *, Q=None, data=None)Source#

Bases: object

Inverses provided data using Minimum Fisher Regularization (MFR) scheme.

Note

The theory and implementation of the MFR are described here.

Parameters:
T(M, N) array_like

Matrix \(\mathbf{T}\in\mathbb{R}^{M\times N}\) of the forward problem (geometry matrix, ray transfer matrix, etc.).

dmatsCollection[Collection[scipy.sparse.spmatrix, scipy.sparse.spmatrix]]

Iterable of pairs of derivative matrices \(\mathbf{D}_i\) and \(\mathbf{D}_j\) along to \(i\) and \(j\) coordinate directions, respectively.

Q(M, M) array_like, optional

Weighted matrix for the residual norm \(\mathbf{Q}\in\mathbb{R}^{M\times M}\), by default None (meaning \(\mathbf{Q} = \mathbf{I}\)). This matrix must be a symmetric positive semi-definite matrix.

data(M, ) array_like, optional

Given data as a vector \(\mathbf{b}\in\mathbb{R}^M\), by default None.

Examples

>>> mfr = Mfr(T, dmats, data=data)

Methods

regularization_matrix(x[, eps, ...])

Compute nonlinear regularization matrix from provided derivative matrices and a solution vector.

solve([x0, derivative_weights, eps, tol, ...])

Solve the inverse problem using MFR scheme.

Attributes

Q

Weighted matrix \(\mathbf{Q}\) for the residual norm.

T

Matrix \(\mathbf{T}\) of the forward problem.

data

Given data as a vector \(\mathbf{b}\).

dmats

List of pairs of derivative matrices \(\mathbf{D}_i\) and \(\mathbf{D}_j\).