from matplotlib.widgets import MultiCursor from pylab import figure, show, pi, arange, sin t = arange(0.0, 2.0, 0.01) s1 = sin(2*pi*t) s2 = sin(4*pi*t) fig = figure() ax1 = fig.add_subplot(211) ax1.plot(t, s1) ax2 = fig.add_subplot(212, sharex=ax1) ax2.plot(t, s2) multi = MultiCursor(fig.canvas, (ax1, ax2), color='r', lw=1) show()