python基本语法2.3--函数及参数传递

# -*- coding: utf-8 -*-

# 函数定义和默认参数
def func(x, y = 500):
    print(x, y)

func(150)
func(100, 200)
func(y = 300, x = 100)

# 可变参数
def func(name, *numbers):
    print(name)
    print(numbers)

func('Tom', 1, 2, 3, 4)

# 关键字参数
def func(name, **kvs):
    print(name)
    print(kvs)

func('Jack', china = 'Beijing', uk = 'London')

# 命名关键字参数
def func(*, china, uk): # *用于和普通参数做分割，*args一样效果
    print(china, uk)

func(china = 'Beijing', uk = 'London')  # 必须传入参数名

# 复杂情况
def func(a, b, c = 0, *args, **kvs):
    print(a, b, c, args, kvs)

func(1, 2)
func(1, 2, 3)
func(1, 2, 3, 'a', 'b')
func(1, 2, 3, 'a', 'b', china = 'Beijing', uk = 'London')
func(1, 2, 3, *('a', 'b'), **{'china':'Beijing', 'uk':'London'})

# 递归的经典例子！
def fib(n):
    if n < 1:
        raise ValueError
    elif (n == 1) or (n == 2):
        return 1
    else:
        return fib(n - 1) + fib(n - 2)

print(fib(1))
print(fib(2))
print(fib(3))
print(fib(4))
print(fib(5))
print(fib(6))