Python zip() Function

Python zip() function returns a zip object, which maps a similar index of multiple containers. It takes iterables (can be zero or more), makes it an iterator that aggregates the elements based on iterables passed, and returns an iterator of tuples.

Python's zip() function is a built-in function that is used to combine two or more iterables into a single iterable. This function takes in any number of iterables (lists, tuples, sets, etc.) as arguments and returns an iterator that aggregates elements from each of the iterables into tuples. Each tuple contains the i-th element from each of the input iterables.

The syntax for using the zip() function is:

Parameters

iterator1, iterator2, iterator3: These are iterator objects that joined together.

Return

It returns an iterator from two or more iterators.

Python zip() Function Example 1

The below example shows the working of zip().

 
numList = [4,5, 6]
strList = ['four', 'five', 'six']

# No iterables are passed
result = zip()

# Converting itertor to list
resultList = list(result)
print(resultList)

# Two iterables are passed
result = zip(numList, strList)

# Converting itertor to set
resultSet = set(result)
print(resultSet)

Output:

[]
{(5, 'five'), (4, 'four'), (6, 'six')}

Explanation: In the above example, we have initialized the lists, i.e., numList (contains integer values) and strList (contains string values) and map the values by using zip().

In the first case, it converts iterator to a list and prints resultList that contains no values.

Then, two iterables are passed in the zip(), i.e., numList, strList and convert iterator to set and return its values.

Python zip() Function Example 2

The below example unzip the values using zip().

 
coordinate = ['x', 'y', 'z']
value = [6, 2, 8, 5, 1]

result = zip(coordinate, value)
resultList = list(result)
print(resultList)
c, v =  zip(*resultList)
print('c =', c)
print('v =', v)

Output:

[('x', 6), ('y', 2), ('z', 8)]
c = ('x', 'y', 'z')
v = (6, 2, 8)

The function takes in any number of iterables as arguments, separated by commas, and returns an iterator that generates tuples containing elements from each of the iterables.

Example 3:

 
names = ['Alice', 'Bob', 'Charlie']
ages = [25, 30, 35]
We can use the zip() function to combine these two lists into a single iterable:
combined = zip(names, ages)
Now, we can iterate over the combined iterable and print out the tuples containing the name and age of each person:
for name, age in combined:
    print(name, age)

Output:

Alice 25
Bob 30
Charlie 35

We can also use the zip() function with more than two iterables. For example, suppose we have three lists:

Example 4:

 
names = ['Alice', 'Bob', 'Charlie']
ages = [25, 30, 35]
heights = [160, 175, 180]
We can combine these three lists using the zip() function:
combined = zip(names, ages, heights)
Now, we can iterate over the combined iterable and print out the tuples containing the name, age, and height of each person:
for name, age, height in combined:
    print(name, age, height)

Output:

Alice 25 160
Bob 30 175
Charlie 35 180

In summary, the zip() function in Python is a powerful tool that allows us to combine two or more iterables into a single iterable. It is a useful function for working with data that is spread across multiple lists or other data structures.

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