boundary_types = p,p
boundary_values = 1,2
initial_gradients =          -2, -0.4,  0.5,    2,   -2,    0,   10, -0.1,  0.3, -0.4,   -3,    2,  0.4, -0.3,  0.1
reflection_path =   (1,1),(2,1),(3,2),(3,3),(2,4),(1,4),(0,3),(1,2),(2,3),(1,4),(1,5),(2,6),(3,6),(4,5),(4,4),(3,3),(4,2)
grid_size = 9
max_radius = 70%
