importmatplotlib.pyplotaspltimportmatplotlib.tickerimportnumpyasnpll=matplotlib.ticker.LogLocator(subs=(1,2,5))### The following code produces a plot with y-axis ticks at the expected locations.fig,ax=plt.subplots()x=np.arange(8)plt.semilogy(x,10**x)ax.yaxis.set_major_locator(ll)ax.yaxis.set_minor_locator(ll)plt.title("Good Plot")plt.show()### The following code produces a plot with no y-axis ticks, which is unexpected and undesired.fig,ax=plt.subplots()x=np.arange(9)# The only change is this lineplt.semilogy(x,10**x)ax.yaxis.set_major_locator(ll)ax.yaxis.set_minor_locator(ll)plt.title("Bad Plot")plt.show()### The problem is isolated to here, which returns correct values in the first case, but np.array([]) in the second case:print(ll.tick_values(1,1e7))print(ll.tick_values(1,1e8))