print("the space_tensor of the last level")
print(low_level.space_tensor)
print(*mg_problem.act_grid_distances)
print("test the is on border function")
is_on_border = low_level.border_function_generator(laplace_stencil)
border_truth = [is_on_border((i,)) for i in range(low_level.evaluable_view(laplace_stencil).size)]
print(border_truth)
# define the smoother from the split smoother class on each level,
# where the last level is solved directly
# omega = 1/np.sqrt(2)
omega = 0.5
l_plus = np.asarray([0, -2.0/omega, 0])
l_minus = np.asarray([1.0, -2.0*(1.0 - 1.0/omega), 1.0])
top_jacobi_smoother = SplitSmoother(l_plus / top_level.h**2,
l_minus / top_level.h**2,
top_level)
mid_jacobi_smoother = SplitSmoother(l_plus / mid_level.h**2,
l_minus / mid_level.h**2,
mid_level)
low_jacobi_smoother = SplitSmoother(l_plus / low_level.h**2,
l_minus / low_level.h**2,
low_level)
low_direct_smoother = DirectSolverSmoother(laplace_stencil, low_level)
# time to test the relaxation methods
print("===== DirectSolverSmoother Test =====")
low_level.rhs[:] = 0.0
low_level.pad()
print("arr:", low_level.arr)
laplace_stencil.modify_rhs(low_level)
print("rhs:", low_level.rhs)
laplace_stencil.modify_rhs(level)
direct_solver.relax()
print("level.arr after direct solution\n", level.mid)
print("test of the solution Ax=b by convolve\n ", laplace_stencil.eval_convolve(level.mid, "same"))
rhs_test = np.zeros(level.rhs.shape)
laplace_stencil.eval_sparse(level.mid, rhs_test)
print("test of the solution Ax=b by sparse matrix application \n", rhs_test)
print("==== SplitSmoother ====")
omega = 2.0/3.0
l_plus = np.asarray([[0, 0, 0],
[0, -4.0/omega, 0],
[0, 0, 0]])
l_minus = np.asarray([[0, 1.0, 0], [1.0, -4.0*(1.0 - 1.0/omega), 1.0], [0., 1., 0.]])
jacobi_smoother = SplitSmoother(l_plus, l_minus, level)
level.mid[:] = 0
jacobi_smoother.relax()
print("level.arr after one jacobi step with modified rhs\n", level.arr)
level.mid[:] = 0.
level.modified_rhs = False
level.rhs[:] = 0.
jacobi_smoother = SplitSmoother(l_plus, l_minus, level)
jacobi_smoother.relax()
print("level.arr after one jacobi step with unmodified rhs\n", level.arr)
# For the test of the level transitioning we define 3 levels
# with different roles but the same borders
n_jacobi_pre = 5
n_jacobi_post = 5
