Further notations and definitions are needed for the FOSLS functional.
For self-containment, we review some of the existing theory for the FOSLS formulation of (1.
the space-angle FOSLS formulation is to minimize the scaled least-squares functional
For the multi-group, anisotropic scattering case, the FOSLS formulation is generalized by using the scaling operator
Two of the advantages of a FOSLS formulation are that it leads to symmetric positive-definite linear systems, and that it is endowed with a computable a posteriori error measure ().
n] - h finite element discretization of the FOSLS formulation was implemented.