--coding:utf-8--

def send(name,address):
return 'package is sent to %s, located in %s' %(name, address)
print(send('winnie','shanghai'))

关键字传递

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def run(name,length, date):
return '%s ran %s on %s' %(name,length,date)

关键字传递时，可以无视参数顺序，名字对了就行。

print(run(length = '5km',date ='11/29/2016',name = 'winnie'))

关键字和位置混用，但要注意位置参数要出现在关键字前面。如果不，那编译器不知道除了几个有名字的，位置的顺序。

print(run('winnie',length = '5km',date ='11/29/2016'))
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winnie ran 5km on 11/29/2016
winnie ran 5km on 11/29/2016
[Finished in 0.2s]

默认值参数

3. 默认值参数：可以给出参数默认值

我们跑团每周二的例行约跑

def runWeekly(name,length, time = 'Tuesday 5：00PM'):
return '%s ran %s on %s' %(name,length,time)
调用：

print(runWeekly('jin','5km'))
print(runWeekly('jin','5km','Wednesday'))
print(runWeekly('jin',time = '5km','Wednesday')) #Error

File "C:pytestSele em1111.py", line 20
print(runWeekly('jin',time = '5km','Wednesday'))
SyntaxError: non-keyword arg after keyword arg
[Finished in 0.2s with exit code 1]
4. 包裹传递

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4. 包裹传递（*/**）

参数被 collect收集，type： tuple

def subselect(*collect):
print collect
print type(collect)

参数被 aa收集，type： dict

def packing(**aa):
#print test
print type(aa)
print aa
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调用：

subselect(['ppe-test-1','dddd'])
packing(a=1,b=2,sub=[11,22])
输出：

<type 'tuple'>
<type 'dict'>
{'a': 1, 'b': 2, 'sub': [11, 22]}
[Finished in 0.2s]
5. 解包

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5.Unpacking with /*

tuple1 = ['test1','test2','test3']
dictionary1 = {'at':'88wi','b':'secondParam','third':'winnie'}
print 'dictionary1 ', dictionary1
def useDict(at,b,third):
print at , b ,third
useDict(**dictionary1) #把字典参数解包此时相当于关键字参数传递名字和函数定义的参数名必须要一一对应
useDict(*tuple1) #把元组解包此时相当于位置参数传递
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【Python学习】函数参数传递方法四种（位置，关键字，默认值，包裹位置，包裹关键字传递）