SpECTRE
v2022.01.03

Subclasses supply variableindependent background data for an elliptic solve. More...
#include <Background.hpp>
Subclasses supply variableindependent background data for an elliptic solve.
Examples for background fields are a background metric, associated curvature quantities, matter sources such as a massdensity in the XCTS equations, or just a source function \(f(x)\) in a Poisson equation \(\Delta u = f(x)\).
Subclasses must define the following compiletime interface:
They define a variables
function that provides the fixedsources in the elliptic equations (see elliptic::protocols::FirstOrderSystem
). The function must have this signature:
It must support being called with a tmpl::list
of all systemvariable tags prefixed with Tags::FixedSource
.
They define a variables
function that provides data for all background quantities, if any are listed in the background_fields
of the system (see elliptic::protocols::FirstOrderSystem
). The function must have this signature:
It must support being called with a tmpl::list
of all background tags. It may use the mesh
and inv_jacobian
to compute numerical derivatives.