*SP*_{N}Equations: Red and Green terms are treated explicitly, equations decouple into*M*`x`*G*separate diffusion equations- DSA Equations: summing over angle and treating Red terms
implicitly leads to
*G*separate diffusion equations, which provide an angle-constant update - LMFG Equation: summing over group and treating Green terms implicitly leads to a single diffusion equation, which provides a spectrum-scaled update
- These equations are solved repeatedly until the Red and Green terms converge

Michael L. Hall