python与算法：两种计算平方根的算法的开销

import time
# 使用牛顿迭代公式计算平方根
def get_sqrt(x,e=10**(-6)):
    y=x
    while abs(y*y-x)>e:
        z=(y+x/y)/2.0
        y=z
    return y
### 使用基础数学的方法求平方根，并与牛顿迭代法进行对比
def base_sqrt(num,e=10**(-6)):
    n=0
    while n*n<num:
        n+=1
    n=n-1
    x=(num-n*n)/(2*n)
    n=n+x
    while abs(num-n*n)>e:
        x=(num-n*n)/(2*n)
        n+=x
    return n

def get_muti_base_sqrt(n):
    t1=time.time()
    for i in range(3,n):
        base_sqrt(i)
    t2=time.time()
    return t2-t1
def get_muti_sqrt(n):
    t1=time.time()
    for i in range(3,n):
        get_sqrt(i)
    t2=time.time()
    return t2-t1
x=list(range(1000,50000,1000))
base_y=[get_muti_base_sqrt(i) for i in x]
sqrt_y=[get_muti_sqrt(i) for i in x]

import matplotlib.pyplot as plt
plt.plot(x,base_y,color='red')
plt.plot(x,sqrt_y,color='green')
plt.legend(["A: base_y", "B: sqrt_y"])
plt.show()