1.多类型传值和冗余参数
多类型传值：
def fun(x,y):
return x +y
print fun(3,5)
8
print fun(*t)
3
def fun(x,y,z):
return x + y + z
t1 = (1,2,3)
fun(*t1)
6
fun(*(2,4,5))
11
fun(1,*t)
4
print t
(1, 2)
fun(x=1,y=3,z=5)
9
>>> dic = {'x':1,'y':3,'z':6}
>>> fun(**dic)
10
冗余参数：
>>> def fun(x,*args,**kwargs):
... print x
... print args
... print kwargs
...
>>> fun(1)
1
()
{}
>>> fun(1,2)
1
(2,)
{}
>>> fun(1,2,3)
1
(2, 3)
{}
>>> t
(1, 2)
>>> fun(1,2,3,'a',[1,2],*t,a=3,**{'t':11,'p':22})
1
(2, 3, 'a', [1, 2], 1, 2)
{'a': 3, 'p': 22, 't': 11}
2.函数的递归调用
递归的注意事项：
必须有最后的默认结果:
if n == 0
递归参数必须向默认结果收敛的：
factorial(n-1)
阶乘脚本：
#!/usr/bin/env python
# -*- coding:utf-8 -*-
# 2018/11/28 11:57
# Feng Xiaoqing
# jiecheng.py
# ======================
def factorial(n):
sum = 0
for i in range(1,n+1):
sum += i
return sum
print factorial(100)
另外一种方法：
def factorial(n):
if n == 0:
return 1
else:
return n * factorial(n-1)
print factorial(5)
求1-100相加的和：
def factorial(n):
if n == 0:
return 0
else:
return n + factorial(n-1)
print factorial(100)