Change the code of the graph so that only integers are displayed on the x-scale and there is a grid of integers on the whole graph plt.plot(ks, k_inertia) plt.plot(ks, k_inertia ,'ro') plt.xlabel('Количество кластеров') plt.ylabel('Инерция')

ax.set_xticks(np.arange(0, 80, 10))
plt.grid(True)