import numpy as np
import matplotlib.pylab as plt
def Leib(n):
return ((-1)**n)/(2*n+1)
x=np.linspace(0,10,11)
y=Leib(x)
y2=np.cumsum(y)
plt.plot(x,y2*4)
plt.show()
print(y2[-1]*4,np.pi,y2[-1]*4-np.pi)
x=np.linspace(0,100,101)
y=Leib(x)
y2=np.cumsum(y)
import matplotlib.pylab as plt
plt.plot(x,y2*4)
plt.show()
print(y2[-1]*4,np.pi,y2[-1]*4-np.pi)
x=np.linspace(0,1000,1001)
y=Leib(x)
y2=np.cumsum(y)
import matplotlib.pylab as plt
plt.plot(x,y2*4)
plt.show()
print(y2[-1]*4,np.pi,y2[-1]*4-np.pi)