数据挖掘与算法 第五次作业

问题：

• 数列：
• a = a1,a2,a3,·····,an
• b = b1,b2,b3,·····,bn
• 求：
• c = a12+b13,a22+b23,a32+b33,·····+an2+bn3

代码：

a = list(range(10))
b =list(range(0,50,5))
c=[]
for i in range(len(a)):
    c.append (a[i] + b[i])
    print(a,b,c)


#用列表+循环实现，并包装成函数
def xhuSum(n):
    a = list(range(n))
    b = list(range(0,5*n,5))
    c = []
    for i in range(len(a)):
        c.append(a[i]**2+b[i]**3)
    return c
print(xhuSum(10))

#用numpy实现，并包装成函数
import numpy
def msnumpy(n):
    a = numpy.arange(n)
    b = numpy.arange(n)
    c = a + b
    return c
print(msnumpy(10))

#对比两种方法实现的效率
from datetime import datetime
start1 = datetime.now()
xhuSum(1000000)
timedelta1 = datetime.now() - start1
print(timedelta1)

start2 = datetime.now()
msnumpy(1000000)
timedelta2 = datetime.now() - start2
print(timedelta2)

timedelta3 = timedelta1-timedelta2
print(timedelta3)

 

运行结果：