The following test code doesn't render the _1 and _2 as double subscript. Is this a bug? import matplotlib.pyplot as plt esno1dB = 10; esno2dB=10 plt.suptitle (r'${E_s/N_0}_1=%g, {E_s/N_0}_2=%g$'%(esno1dB,esno2dB)) plt.show()