functional programming - scala gather a list of pair combination -



functional programming - scala gather a list of pair combination -

given following:

map( x -> list( (option[ob1], option[obja]), (option[obj1], option[objb]), (option[obj2], option[obja]), (option[obj2], option[objb]), (..., ...) ))

i need collect , grouping combinations pair of 2 lists (while keeping map , key portion same now):

map (x -> ( list(obj1, obj2, obj3 ...), list(obja, objb ...) )

so in other words, need perform sort of opposite operation of creating combinations of 2 lists , need "original" 2 lists containing each unique element. have tried various combinations of unzip , mapping no success.

sounds you're looking map:

.mapvalues(_.unzip).mapvalues{ case (a, b) => (a.distinct, b.distinct) }

if need sorting, can chain against distinct methods.

scala functional-programming

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