  The discrete spectra of certain two-dimensional Schrodinger operators are
numerically calculated. These operators have interesting spectral properties,
i.e. their kernels are multi-dimensional and the deformations of potentials via
the Novikov-Veselov equation (a two-dimensional generalization of the
Korteweg-de Vries equation) lead to blowups, and are obtained by the Moutard
transformation. The calculations supply the numerical evidence for certain
statements on integrable systems related to the 2D Schrodinger operator. The
numerical scheme is applicable to a general 2D Schrodinger operator with fast
decaying potential.
