Module kernel 

Kernel implementations for SparseIR

This module provides kernel implementations for analytical continuation in quantum many-body physics. The kernels are used in Fredholm integral equations of the first kind.

u(x) = integral of K(x, y) v(y) dy

where x ∈ [xmin, xmax] and y ∈ [ymin, ymax].

In general, the kernel is applied to a scaled spectral function rho’(y) as:

integral of K(x, y) rho’(y) dy,

where ρ’(y) = w(y) ρ(y). The weight function w(y) transforms the original spectral function ρ(y) into the scaled version ρ’(y) used in the integral equation.

Structs

LogisticKernel

Logistic kernel for fermionic analytical continuation

LogisticSVEHints

SVE hints for LogisticKernel

RegularizedBoseKernel

Regularized bosonic analytical continuation kernel

RegularizedBoseSVEHints

SVE hints for RegularizedBoseKernel

Enums

SymmetryType

Traits

AbstractKernel

Trait for general kernels (both centrosymmetric and non-centrosymmetric)

CentrosymmKernel

Trait for centrosymmetric kernels

KernelProperties

Trait for kernel type properties (static characteristics)

SVEHints

Trait for SVE (Singular Value Expansion) hints

Functions

compute_logistic_kernel