#!/usr/bin/python3
import numpy as np
import math
import matplotlib.pyplot as plt
import mpl_toolkits.mplot3d as Axes3D

def f(x,y):
    return ((x-1)**2+y**2)


x = np.linspace(-2,2,100)
y = np.linspace(-2,2,100)
X,Y = np.meshgrid(x,y)

plt.pcolor(X,Y,f(X,Y))
plt.show()