boundary_types = p,-g
boundary_values = 2,-1
initial_gradients =      -2.4, -2.4,   50,  3.5,  0.3,    0,-0.3
reflection_path = (2,2),(2,3),(3,2),(3,3),(3,2),(4,3),(3,3),(4,3)
grid_size = 5
max_radius = 80%
