Полином Лагранжа 1

import numpy as np
import matplotlib.pyplot as plt
x=np.array([0,1,2,3,4,5], dtype=float)
y=np.array([0.1,0.6,1,6,-2,-3], dtype=float)
def lagranz(x,y,t):
    z=0
    for j in range(len(y)):
        p1=1; p2=1
        for i in range(len(x)):
            if i==j:
                p1=p1*1; p2=p2*1
            else:
                p1=p1*(t-x[i])
                p2=p2*(x[j]-x[i])
        z=z+y[j]*p1/p2
    return z
def integr(a,b,dx):
    points=np.arange(a,b,dx)
    summ=0
    for x_cur in points:
        print x_cur
        for x_cur in points:
            summ+=lagranz(x,y,x_cur)*dx
        return summ

xnew=np.linspace(np.min(x),np.max(x),100)
ynew=[lagranz(x,y,i) for i in xnew]
plt.plot(x,y,'o',xnew,ynew)
plt.grid(True)
plt.show()

print integr(np.min(x),np.max(x),0.1)
print integr(0,1,0.1)