intersection
set.intersection
Returns a NEW set containing only elements found in s AND in every argument. Method form accepts any iterables; & requires sets.
s.intersection(*others) | s & otherParameters
| Parameter | Purpose |
|---|---|
| *others | Iterables (method) or sets (operator) to intersect with |
| returns | A new set of common elements |
Examples
>>> {1, 2, 3} & {2, 3, 4}
{2, 3}Common elements only.
>>> {1, 2, 3}.intersection([2, 3], [3, 4])
{3}Multiple iterables — only elements in ALL of them survive.
>>> {1, 2} & {3, 4}
set()Disjoint sets yield the empty set.
>>> {1, 2, 3}.intersection('23')
set()Type matters — int 2 and str '2' are different elements.
Gotcha
& requires both sides to be sets; use .intersection() for a list/tuple/iterable. Element equality respects type — 1 and '1' are distinct.
Related methods
set.intersection_update
Updates s in place, keeping only elements found in s AND every given iterable. The method form accepts iterables; &= requires sets.
set.union
Returns a NEW set containing every element that appears in s or any of the arguments. The method accepts any iterable(s); the | operator requires all operands to be sets or frozensets.
set.difference
Returns a NEW set with elements from s that are NOT in any of the arguments. Method form takes iterables; - requires sets.
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