Python SET Comprehension With Examples

What is Comprehension?

?We create a sequence from a given sequence is called comprehension.

?Sequence means list, tuple, string and range.

?We can also create a new dictionary from existing dictionary.

?Some sequence allow comprehension but some not.

Why need of Comprehension?

?Simple way to create new sequence

?Filtering & Searching

?One line of code

?Fastest way

?Python set comprehension means, creating a new set from another iterabel object like list, range function etc.

?On the basis of condition we can create a new set from created (given) set or other iterable object.

?We can filter a old set to get required elements / items to store in a new set.

?It is fastest way and one line code to create new set from given set on the basis of some condition.

Syntax

newSet = {expression for item/element in sequence}

SET Comprehension Syntax

newSet = {expression for item/element in sequence}

newSet = {expression for item/element in sequence if statement}

newSet = {expression if statement else statement for item/element in sequence}

newSet = {expression for item/element in sequence nested if statement}

SET Comprehension Example

Examples

lst = [3, 1, 5, 6, 7, 8, 9, 0]

set1 = {x+1 for x in lst } # simple

lst = [‘yellow', ‘pink', ‘gray', ‘white', ‘black']

new_set2 = {x for x in names if ‘a' in x} # if statement

set3 = {“even" if i%2==0 else “odd" for i in range(20)} # if else statement

set4 = {x for x in range(50) if x % 2 == 0 if x % 5 == 0} # nested if statement