Iterate over a list in Python


In this article, we will learn about iterating/traversing over a list in Python 3.x. Or earlier.

A list is an ordered sequence of elements. It is a non-scalar data structure and mutable in nature. A list can contain distinct data types in contrast to arrays storing elements belonging to the same data types.

Method 1: Using iterable without index

Example

list_inp = ['t','u','t','o','r','i','a','l','s','p','o','i','n','t']

# Iterate over the list
for value in list_inp:
   print(value, end='')

Method 2: Using general way via index

Example

list_inp = ['t','u','t','o','r','i','a','l','s','p','o','i','n','t']

# Iterate over the list
for value in range(0,len(list_inp)):
   print(list_inp[value], end='')

Method 3: Using the enumerate type

Example

list_inp = ['t','u','t','o','r','i','a','l','s','p','o','i','n','t']

# Iterate over the list
for value,char in enumerate(list_inp):
   print(char, end='')

Method 4: Using negative indexes

Example

list_inp = ['t','u','t','o','r','i','a','l','s','p','o','i','n','t']

# Iterate over the list
for value in range(-len(list_inp),0):
   print(list_inp[value], end='')

All the above four methods yeilds the output displayed below.

Output

tutorialspoint

Method 5: Using sliced lists

Example

list_inp = ['t','u','t','o','r','i','a','l','s','p','o','i','n','t']

# Iterate over the list

for value in range(1,len(list_inp)):
   print(list_inp[value-1:value], end='')
print(list_inp[-1:])

Output

['t']['u']['t']['o']['r']['i']['a']['l']['s']['p']['o']['i']['n']['t']

Conclusion

In this article, we learnt about iteration/traversal over a list data type. Also, we learnt about various implementation techniques.

raja
Published on 07-Aug-2019 08:04:46
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