Ds\Set::intersect
(PECL ds >= 1.0.0)
Ds\Set::intersect — Creates a new set by intersecting values with another set.
説明
public Ds\Set Ds\Set::intersect
( Ds\Set
$set
)
Creates a new set using values common to both the current instance and another set.
In other words, returns a copy of the current instance with all values removed that
are not in the other set.
A ∩ B = {x : x ∈ A ∧ x ∈ B}
パラメータ
-
set -
The other set.
返り値
The intersection of the current instance and another set.
例
例1 Ds\Set::intersect() example
<?php
$a = new \Ds\Set([1, 2, 3]);
$b = new \Ds\Set([3, 4, 5]);
var_dump($a->intersect($b));
?>
上の例の出力は、 たとえば以下のようになります。
object(Ds\Set)#3 (1) {
[0]=>
int(3)
}
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