> My attempts to compile it in pythran are failing. I think roll doesn't > like partial grids, I know roll was added recently so maybe there's a > bug here? > > This works: > partial_update = grid # using original full grid > roll1 = np.roll(partial_update, +1, 0) > print roll1.dtype > This fails at compile time: > partial_update = grid[i:j, :] # using partial grid > roll1 = np.roll(partial_update, +1, 0) > print roll1.dtype Can you try the roll-bug branch? It should be OK.