An M-partial intersection (for M > 0) of N sets is a set elements in which are contained in at least M initial sets.
For any N sets:
- 1-partial intersection is equivalent to the union of these sets.
- N-partial intersection is equivalent to the common (complete) intersection of these sets.
- For any M > N M-partial intersection always equals to the empty set.
- Simple integer sets example
- Iterable integer sets example
- Mixed iterable sets example
- Multisets example
Given: sets A, B, C, D (N = 4).
$a = [1, 2, 3, 4, 5];
$b = [1, 2, 10, 11];
$c = [1, 2, 3, 12];
$d = [1, 4, 13, 14];It is equivalent to A ∪ B ∪ C ∪ D.
use Smoren\PartialIntersection\IntegerSetArrayImplementation;
$r = IntegerSetArrayImplementation::partialIntersection(1, $a, $b, $c, $d);
// [1, 2, 3, 4, 5, 10, 11, 12, 13, 14]
use Smoren\PartialIntersection\IntegerSetArrayImplementation;
$r = IntegerSetArrayImplementation::partialIntersection(2, $a, $b, $c, $d);
// [1, 2, 3, 4]
use Smoren\PartialIntersection\IntegerSetArrayImplementation;
$r = IntegerSetArrayImplementation::partialIntersection(3, $a, $b, $c, $d);
// [1, 2]It is equivalent to A ∩ B ∩ C ∩ D.
use Smoren\PartialIntersection\IntegerSetArrayImplementation;
$r = IntegerSetArrayImplementation::partialIntersection(4, $a, $b, $c, $d);
// [1]Equals to an empty set.
use Smoren\PartialIntersection\IntegerSetArrayImplementation;
$r = IntegerSetArrayImplementation::partialIntersection(5, $a, $b, $c, $d);
// []$a = [1, 2, 3, 4, 5];
$b = [1, 2, 10, 11];
$c = [1, 2, 3, 12];
$d = [1, 4, 13, 14];
use Smoren\PartialIntersection\IntegerSetIterableImplementation;
$r = IntegerSetArrayImplementation::partialIntersection(1, $a, $b, $c, $d);
print_r(iterator_to_array($r));
// [1, 2, 3, 4, 5, 10, 11, 12, 13, 14]
$r = IntegerSetArrayImplementation::partialIntersection(2, $a, $b, $c, $d);
print_r(iterator_to_array($r));
// [1, 2, 3, 4]
$r = IntegerSetArrayImplementation::partialIntersection(3, $a, $b, $c, $d);
print_r(iterator_to_array($r));
// [1, 2]
$r = IntegerSetArrayImplementation::partialIntersection(4, $a, $b, $c, $d);
print_r(iterator_to_array($r));
// [1]
$r = IntegerSetArrayImplementation::partialIntersection(5, $a, $b, $c, $d);
print_r(iterator_to_array($r));
// []$a = ['1', 2, 3, 4, 5];
$b = ['1', 2, 10, 11];
$c = ['1', 2, 3, 12];
$d = ['1', 4, 13, 14];
use Smoren\PartialIntersection\MixedSetIterableImplementation;
$r = MixedSetIterableImplementation::partialIntersection(true, 1, $a, $b, $c, $d);
print_r(iterator_to_array($r));
// ['1', 2, 3, 4, 5, 10, 11, 12, 13, 14]
$r = MixedSetIterableImplementation::partialIntersection(true, 2, $a, $b, $c, $d);
print_r(iterator_to_array($r));
// ['1', 2, 3, 4]
$r = MixedSetIterableImplementation::partialIntersection(true, 3, $a, $b, $c, $d);
print_r(iterator_to_array($r));
// ['1', 2]
$r = MixedSetIterableImplementation::partialIntersection(true, 4, $a, $b, $c, $d);
print_r(iterator_to_array($r));
// ['1']
$r = IntegerSetArrayImplementation::partialIntersection(true, 5, $a, $b, $c, $d);
print_r(iterator_to_array($r));
// []Note: If input collections contains duplicate items, then multiset intersection rules apply.
$a = [1, 1, 1, 1, 1];
$b = [1, 2, 3, 4, 5, 1, 2, 3, 4, 5];
$c = [5, 5, 5, 5, 5, 1, 5, 5, 1];
use Smoren\PartialIntersection\MultisetIterableImplementation;
$r = MultisetIterableImplementation::partialIntersection(true, 1, $a, $b, $c);
print_r(iterator_to_array($r));
// [1, 1, 1, 1, 1, 2, 2, 3, 3, 4, 4, 5, 5, 5, 5, 5, 5, 5]
$r = MultisetIterableImplementation::partialIntersection(true, 2, $a, $b, $c);
print_r(iterator_to_array($r));
// [1, 1, 5, 5]
$r = MultisetIterableImplementation::partialIntersection(true, 3, $a, $b, $c);
print_r(iterator_to_array($r));
// [1, 1]
$r = MultisetIterableImplementation::partialIntersection(true, 4, $a, $b, $c);
print_r(iterator_to_array($r));
// []composer install
composer test-init
composer test