I used to be foolish enough to tell the difference between * and ** when passing parameters in Python. As soon as you see * and **, the concept of pointers comes to mind. I finally figured it out today. record it
# -*- coding:utf-8 -*-
'''
Parameter passing:
package transfer
'''
'''
Package location parameter: what is collected is a tuple
'''
def
package_position
(*
all_arguments
):
print
all_arguments
# print the result as (1, 4, 6)
for
k
in
all_arguments:
print
k
'''
Package keyword parameter: what is collected is a dictionary
'''
def
package_keyword
(**
all_arguments
):
print
all_arguments
#Print result is {'a': 1, 'c': 3, 'b': 2}
#print k,v
for
k,v
in
all_arguments.items():
all_arguments[k] = v +
1
'''
Mixed use of positional parameter passing and keyword parameter passing
'''
def
packeage_min
(*
position
,**
keywords
):
print position
print keywords
#打印结果
#(1, 2, 3)
#{'a': 7, 'c': 9, 'b': 8}
'''
解包裹
'''
def
unpackage(
a,
b,
c):
print (a,b,c)
if
__name__ ==
'__main__':
#package_position(1,4,6)
args2={
'a':
4,
'b':
5,
'c':
6}
package_keyword(**args2)
#packeage_min(1,2,3,a=7,b=8,c=9)
args = (
1,
3,
4)
#unpackage(*args) #在args前加上*，来提醒Python，我想把元组拆成三个元素，每个元素对应函数的一个位置参数
args2={
'a':
4,
'b':
5,
'c':
6}
#unpackage(**args2) #在args2前加上**，让字典的每个键值对作为一个关键字传递给函数