python高级特性-迭代

>>> d={'a':1,'b':2,'c':3}

#输出values

>>> for v in d.values():
 ...     print v
 ... 
 1
 3
 2

>>> for k, v in d.items():
...      print k,v
... 
#输出
a 1
c 3
b 2

>>> for a in 'adfa':
...      print a
... 
a
d
f
a

>>>from collections import Iterable
#判断字符串是否可迭代
>>>isinstance('abc',Iterable)
#输出
True
#判断list是否可迭代

>>> for i,value in enumerate(['a','b','c']):
...      print(i,value)
... 
(0, 'a')
(1, 'b')
(2, 'c')
>>> for i,value in enumerate(['a','b','c']):
...      print  i,value
... 
0 a
1 b
2 c

>>> for x,y in [(1,1),(2,3),(4,5)]:
...      print x,y
... 
1 1
2 3
4 5