GeezerVison is showing github.com — learn-python/src/data_types/test_sets.py at master · anandme/learn-python

Expand file tree

test_sets.py

Copy path

More file actions

Latest commit

History

70 lines (48 loc) · 2.27 KB

test_sets.py

Copy path

File metadata and controls

70 lines (48 loc) · 2.27 KB

Raw

Copy raw file

Download raw file

Open symbols panel

Edit and raw actions

"""Sets.

@see: https://www.w3schools.com/python/python_sets.asp

@see: https://docs.python.org/3.7/tutorial/datastructures.html#sets

A set is a collection which is unordered and unindexed.

In Python sets are written with curly brackets.

Set objects also support mathematical operations like union, intersection, difference, and

symmetric difference.

"""

def test_sets():

"""Sets"""

fruits_set = {"apple", "banana", "cherry"}

assert isinstance(fruits_set, set)

# It is also possible to use the set() constructor to make a set.

# Note the double round-brackets

fruits_set_via_constructor = set(("apple", "banana", "cherry"))

assert isinstance(fruits_set_via_constructor, set)

def test_set_methods():

"""Set methods"""

fruits_set = {"apple", "banana", "cherry"}

# You may check if the item is in set by using "in" statement

assert "apple" in fruits_set

assert "pineapple" not in fruits_set

# Use the len() method to return the number of items.

assert len(fruits_set) == 3

# You can use the add() object method to add an item.

fruits_set.add("pineapple")

assert "pineapple" in fruits_set

assert len(fruits_set) == 4

# Use remove() method to remove an item.

fruits_set.remove("pineapple")

assert "pineapple" not in fruits_set

assert len(fruits_set) == 3

# Demonstrate set operations on unique letters from two word:

first_char_set = set('abracadabra')

second_char_set = set('alacazam')

assert first_char_set == {'a', 'r', 'b', 'c', 'd'} # unique letters in first word

assert second_char_set == {'a', 'l', 'c', 'z', 'm'} # unique letters in second word

# Letters in first word but not in second.

assert first_char_set - second_char_set == {'r', 'b', 'd'}

# Letters in first word or second word or both.

assert first_char_set | second_char_set == {'a', 'c', 'r', 'd', 'b', 'm', 'z', 'l'}

# Common letters in both words.

assert first_char_set & second_char_set == {'a', 'c'}

# Letters in first or second word but not both.

assert first_char_set ^ second_char_set == {'r', 'd', 'b', 'm', 'z', 'l'}

# Similarly to list comprehensions, set comprehensions are also supported:

word = {char for char in 'abracadabra' if char not in 'abc'}

assert word == {'r', 'd'}