compiletime load "module_ppp.so";
PPP obj = {};

obj.read("density.pos",  "n");
obj.read("velocity.pos", "v");

obj.create_vector("flux", n*v_x, n*v_y, n*v_z);

obj.xy_plane(0, 10, "nearest_neighbour");

obj.write_pos_scalar_binary("flux-Z.pos", "Vertical flux [1/m^2 s]", flux_z);
obj.write_pos_scalar_binary("flux-Z-relative.pos", "Relative Vertical flux [%]", 
                            100*flux_z/flux_z_max);