I have a list of case class :
case class MyClass(id1: String, id2: String, nb: Int)
val myList = List(
MyClass("id1", "id2", 3),
MyClass("id3", "id4", 4),
MyClass("id2", "id1", 3), // <- Delete this one (dedup with MyClass("id1", "id2", 3))
MyClass("id4", "id2", 4), // <- Delete this one (dedup with MyClass("id2", "id4", 4))
MyClass("id5", "id6", 12)
)
myList.foldLeft(List[MyClass]()) {
(acc, elem) =>
if (myList.contains(MyClass(elem.id2, elem.id1, elem.nb))) {
acc
} else {
acc : elem
}
}
I want to delete duplicates if id1
and id2
is inverted with same nb
value (as describe in code comment)
I tried with foldLeft
but it's very slow (my list has 400k entries)
Anyone has a magic solution for this use case ?
Thanks !
CodePudding user response:
If only ids are considered for equality - one option is to use distinctBy
on "ordered" tuple:
val result = myList.distinctBy(c => if (c.id1 > c.id2) (c.id1, c.id2) else (c.id2, c.id1))
For case when all three members should be considered - I would "reorder" ids in MyClass
and use distinct
:
val result = myList.map {
case MyClass(id1, id2, v) if id1 > id2 => MyClass(id2, id1, v)
case c => c
}.distinct