

Domain-decomposed deflation preconditioner

check1        Check of the DFL_BLOCKS grid geometry arrays.

check2        Check of the programs in the module dfl_subspace.c.

check3        Check of the solver for the little Dirac equation.

check4        Check and performance of the deflated SAP+GCR solver.

The programs check1 and check2 accept the option -bc <type> that allows the
type of boundary condition to be chosen at runtime. When the option is not
set, open boundary conditions are assumed.

The option may be set but has no effect in the case of check3 and check4 (the
boundary conditions are selected through the input parameter file in these
cases).
