python enumerate 用法小结

enumerate应用实例：

该实例中，line 是个 string 包含 0 和 1，要把1都找出来：

方法一：

?

1

2

3

4

5

6

7

defread_line(line):

  sample={}

  n=len(line)

  fori inrange(n):

    ifline[i]!='0':

      sample[i]=int(line[i])

  returnsample

方法二：

1

2

3

4

5

defxread_line(line):

  return((idx,int(val))foridx, val inenumerate(line)ifval !='0')

  

printread_line('0001110101')

printlist(xread_line('0001110101'))

i = 0
seq = ['one', 'two', 'three']
for element in seq:
    print i, seq[i]
    i += 1
#0 one
#1 two
#2 three


print '============'
seq = ['one', 'two', 'three']
for i, element in enumerate(seq):
    print i, seq[i]
    
print '============'
for i,j in enumerate('abc'):
    print i,j
#0 a
#1 b
#2 c


print '============'
def _treatment(pos, element):
    return '%d: %s' %(pos, element)


seq = ['one', 'two', 'three']
print [_treatment(i, e1) for i, e1 in enumerate(seq)]

?