Copy & Paste de esa página
$ ipython --pylab
Python 2.7.4 (default, Apr 19 2013, 18:28:01)
Type "copyright", "credits" or "license" for more information.
IPython 0.13.2 -- An enhanced Interactive Python.
? -> Introduction and overview of IPython's features.
%quickref -> Quick reference.
help -> Python's own help system.
object? -> Details about 'object', use 'object??' for extra details.
Welcome to pylab, a matplotlib-based Python environment [backend: Agg].
For more information, type 'help(pylab)'.
In [1]: from scipy import special, optimize
In [2]: f = lambda x: -special.jv(3, x)
In [3]: sol = optimize.minimize(f, 1.0)
In [4]: x = linspace(0, 10, 5000)
In [6]: plot(x, special.jv(3, x), '-', sol.x, -sol.fun, 'o')
In [7]: savefig('plot.png', dpi=96)
Como puedes ver lo único que tienes que hacer es obtener el óptimo y superponerlo a la gráfica.
Saludos
F. Palm