Python: enumerate() function
enumerate() function
The enumerate() function returns an enumerate object. iterable must be a sequence, an iterator, or some other object which supports iteration.
Note: The __next__() method of the iterator returned by enumerate() returns a tuple containing a count (from start which defaults to 0) and the values obtained from iterating over iterable.
Version:
(Python 3)
Syntax:
enumerate(iterable, start=0)
Parameter:
Name | Description |
---|---|
iterable | A sequence, an iterator, or some other object which supports iteration |
start | A Number. Defining the start number of the enumerate object. Default 0.If start is omitted, 0 is taken as start. |
Return value:
Return an enumerate object.
Example: Python enumerate() function
<<< seasons = ['Spring', 'Summer', 'Fall', 'Winter']
<<< list(enumerate(seasons))
[(0, 'Spring'), (1, 'Summer'), (2, 'Fall'), (3, 'Winter')]
<<< list(enumerate(seasons, start=1))
[(1, 'Spring'), (2, 'Summer'), (3, 'Fall'), (4, 'Winter')]
Equivalent to:
def enumerate(sequence, start=0):
n = start
for elem in sequence:
yield n, elem
n += 1
Example: Python enumerate() function
fruits = ['Mango', 'Apple', 'Orange', 'Peach']
print(list(enumerate(fruits)))
print(list(enumerate(fruits, start=1)))
Output:
[(0, 'Mango'), (1, 'Apple'), (2, 'Orange'), (3, 'Peach')] [(1, 'Mango'), (2, 'Apple'), (3, 'Orange'), (4, 'Peach')]
Example:
Fruits = ['Apple', 'Mango', 'Orange']
enumerateFruits = enumerate(Fruits)
print(type(enumerateFruits))
# converting to list
print(list(enumerateFruits))
# changing the default counter
enumerateFruits = enumerate(Fruits, 10)
print(list(enumerateFruits))
Output:
<class 'enumerate'> [(0, 'Apple'), (1, 'Mango'), (2, 'Orange')] [(10, 'Apple'), (11, 'Mango'), (12, 'Orange')]
Example: Looping Over an Enumerate object
Fruits = ['Apple', 'Mango', 'Orange']
for item in enumerate(Fruits):
print(item)
print('\n')
for count, item in enumerate(Fruits):
print(count, item)
print('\n')
# changing default start value
for count, item in enumerate(Fruits, 50):
print(count, item)
Output:
(0, 'Apple') (1, 'Mango') (2, 'Orange') 0 Apple 1 Mango 2 Orange 50 Apple 51 Mango 52 Orange
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Documentation references for the modules, constants and functions used above:
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