  We present two techniques novel in numerical methods. The first technique
compiles the domain of the numerical methods as a discretized volume. Congruent
elements are glued together to compile the domain over which the solution of a
boundary value problem is sought. We associate a group and a graph to that
volume. When the group is symmetry of the boundary value problem under
investigation, one can specify the structure of the solution, and find out if
there are equispectral volumes of a given type. The second technique uses a
complex mapping to transplant the solution from volume to volume and a
correction function. Equation for the correction function is given. A simple
example demonstrates the feasibility of the suggested method.
