[en] 1 - Description of program or function: VALE is a multigroup neutron diffusion code for solving two- and three-dimensional problems in trigonal geometries. It is a companion code module to the VENTURE neutronics code module in the BOLD VENTURE code system. VALE is a stand-alone code that can be run independently of the BOLD VENTURE system. A variety of types of problems may be solved: the usual neutron flux eigenvalue problem, or a direct criticality search on buckling, on a reciprocal velocity absorber (prompt mode), or on nuclide concentrations. The adjoint problem and fixed source problems may be solved, as well as the dominating higher harmonic, or the importance problem for an arbitrary fixed source. Also implemented is a parametrized formulation that allows part of the absorption term to lie off the matrix diagonal (Taylor series, linear flux, and linear finite element equation formulation methods). The mesh points are located at the material junctures (mesh edge) on planes and mesh centered between planes. The mesh may be 120, 60, or 30 degrees. It is not necessary to treat a parallelogram. With 60 degree mesh point arrangement, only a triangle, or a truncated triangle may be treated. With 30 degree mesh arrangement, a pie shaped section may be treated. There is provision for the more commonly used boundary conditions including the repeating boundary, 180 degree rotational symmetry, and the rotational symmetry conditions for the 30 degree, 60 degree, and 120 degree triangular grids on planes. 2 - Method of solution: Inner-outer iterations are done with restrained line over-relaxation, and asymptotic flux extrapolation done when distinct error modes are established. Normally the eigenvalue of a problem is calculated each outer iteration from an overall neutron balance; however, source ratios are used in some situations. 3 - Restrictions on the complexity of the problem: The large data arrays in VALE are variably dimensioned. The size of problems that may be run are restricted only by the size of the memory available