Python iter() Function

The Python iter() function is a built-in function that is used to obtain an iterator from an iterable object. An iterable is an object that enables us to access one item at a time by iterating over them, such as lists, tuples, strings, etc.

Syntax

Following is the syntax of the Python iter() function

iter(object, sentinel)

Parameters

The Python iter() function accepts two parameters

• object It represents an object such as a list, string, or tuple.

• sentinel It is an optional parameter. When the sentinel value is provided, iteration will continue until the value returned by the iterator matches the sentinel.

Return Value

The Python iter() function returns an iterator object.

iter() Function Examples

Practice the following examples to understand the use of iter() function in Python:

Example: List to Iterator Using iter() Function

In the code below, we are converting a given list into an iterator object by using the iter() function and then, printing the first two elements with the help of next() function.

numericLst = [55, 44, 33, 22, 11]
iteration = iter(numericLst)
print("The first two items from the iterator is:")
print(next(iteration)) 
print(next(iteration))

Following is an output of the above code

The first two items from the iterator is:
55
44

Example: iter() Function With for Loop

The code below demonstrates how to use iter() function with the for loop. Here, we are displaying the elements of the specified list after converting it to iterator object.

numericLst = [55, 44, 33, 22, 11]
iteration = iter(numericLst)
print("All items from the iterator are:")
for item in iteration:
   print(item)

Output of the above code is as follows

All items from the iterator are:
55
44
33
22
11

Example: Tuple to Iterator Using iter() Function

In the code below a tuple is created and then converted into an iterator object using iter() method. Furthermore, we display the first two elements of this object with the help of "for" and "if" loops.

fruitTuple = ("Grapes", "Orange", "Banana", "Apple")
iterator = iter(fruitTuple)
print("The first two items from the iterator are:")
counter = 0
for item in iterator:
   if counter < 2:
      print(item)
      counter += 1
   else:
      break

Following is the output of the above Python code

The first two items from the iterator are:
Grapes
Orange

Example: iter() Function With String

The iter() method can also be used with the string to display its characters one at a time as illustrated in the below example.

orgName = "TutorialsPoint"
iterator = iter(orgName)
print("The characters of the given string are:")
for item in iterator:
   print(item)

The above program, on executing, displays the following output

The characters of the given string are:
T
u
t
o
r
i
a
l
s
P
o
i
n
t