ax = plt.axes()
df['span'] = df.index // 3 # Assign identical markers to each span
df.groupby('span').apply(lambda x: x.plot(x='A', y='B', legend=False, ax=ax)
plt.show() # If not in ipython
ax = df.iloc[:3, [0,1]].plot('A', 'B')
df.iloc[3:6, [0,1]].plot('A', 'B',ax = ax)
df.iloc[6:9, [0,1]].plot('A', 'B',ax = ax)