names = ['one', 'two', 'three', 'four', 'five']
x_tick_location = np.arange(np.min(x), np.max(x) + 0.001, 2.0)
x_tick_labels = [names[x.index(xi)] for xi in x_tick_location]
plt.xticks(x_tick_location, x_tick_labels, rotation='25')
How can I increase the frequency of xticks/ labels for dates on a bar plot?