#Rosenbrock_minimum.py
#
#This example works with scipy from version 0.7.0 to 0.9.0
# In later versions fmin has been consolidated with other methods
# in the minimize function
#Python 2.7.3
#Rosenbrock function of 2 variables:

def rosenbrock(parms):
      x,y = parms
      return (1-x)**2 + 100* (y-x**2)**2

#minimize the function:
from scipy.optimize import fmin
import numpy as np

x0 = np.array([4,-3]) #Start searching at point (4,-3)
res = fmin( rosenbrock, x0, xtol= 1e-8 )

print res