Detailed explanation on the usage of enumerate function in Python

enumerateFunction is used to traverse the elements in the sequence and their subscripts. It is mostly used to get the count in the for loop. The enumerate parameter is a traversable variable, such as string , list, etc.

Generally, for a list or array when both index and elements need to be traversed , it will be written like this:

for i in range (0,len(list)): 
  print i ,list[i]

But this method is a bit cumbersome. Using the built-in enumerrate function will be more direct and elegant. Let’s first look at the definition of enumerate. :

def enumerate(collection): 
  'Generates an indexed series: (0,coll[0]), (1,coll[1]) ...'   
   i = 0 
   it = iter(collection) 
   while 1: 
   yield (i, it.next()) 
   i += 1

enumerate will group the array or list into an index sequence. This makes it more convenient for us to obtain the index and index content as follows:

for index，text in enumerate(list): 
  print index ,text

Code Example 1:

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

0 one

1 two

2 three

##Code example 2:

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

0 one

1 two

2 three

##Code example 3:

for i,j in enumerate('abc'):
    print i,j

0 a

1 b

2 c

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