Python for Java Programmers
Chapter 5: Sets and dictionaries
Set operations
Python provides overloaded operators for various set operations. Since set is also an object, some of these are also available as methods. I will let you explore these on your own.
| Operation | Math Notation | Python Operator | Object Methods |
|---|---|---|---|
| Union | A \cup B | a_set | b_set |
a_set.union(b_set) |
| Intersection | A \cap B | a_set & b_set |
a_set.intersection(b_set) |
| Difference | A \setminus B | a_set - b_set |
a_set.difference(b_set) |
| Symmetric difference | A \triangle B | a_set ^ b_set |
a_set.symmetric_difference(b_set) |
| Membership | x \in B | x in b_set |
|
| Non-membership | x \notin B | x not in b_set |
|
| Proper Subset | A \subset B | a_set < b_set |
|
| Subset | A \subseteq B | a_set <= b_set |
a_set.issubset(b_set) |
| Proper Superset | A \supset B | a_set > b_set |
|
| Superset | A \supseteq B | a_set >= b_set |
a_set.issuperset(b_set) |