Here is a list of all documented files with brief descriptions:

chronometer.h
electrostatSolver.h	Solver for electrostatic problem when STT is required header containing electrostatSolver class. It uses biconjugate stabilized gradient with diagonal preconditioner. The solver is only called once to compute voltages V for each nodes of the mesh, when STT computation is involved
element.h
expression_parser.h
facette.h	Namespace Facette header containing Fac class, and some constants and a less_than operator to redo orientation of triangular faces
feellgoodSettings.h	Many settings to give some parameters to the solver, boundary conditions for the problem, the output file format wanted by the user. This is done mainly with the class Settings
fem.h	Principal header, contains the struct fem This file is called by many source files in feellgood. It does also contains the definition of many constants for the solver, and for scalfmm
fmm_demag.h	This header is the interface to scalfmm. Its purpose is to prepare an octree for the application of the fast multipole algorithm, and to compute the demag field
linear_algebra.h	Secondary header, it grabs altogether the linear algebra by the solver to apply fem method It encapsulates the calls to eigen BiCGSTAB solver, the assemblage and projection of the matrix for all elements projection and matrix assembly is multithreaded for tetrahedron, monothread for facette
log-stats.h
mesh.h	Class mesh, readMesh is expecting a mesh file in gmsh format either text or binary, from version 2.2 to the latest 4.1. The mesh has to use only first order tetraedrons and triangular facettes, mixed meshes are not allowed
meshUtils.h
node.h	Header to define struct Node
spinTransferTorque.h
tags.h
tetra.h	Namespace Tetra header containing Tet class, some constants, and integrales
time_integration.h