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How to find the match element in tuple and concat the array.
f#

Dear All:
I need a function to do the following job:
let a1 = [| ("A", [|1.0f|]); ("B", [|1.0f; 2.0f|]); ("C", [|1.0f; 2.0f; 3.0f|]) |]
let a2 = [| ("C", [|4.0f; 5.0f|]); ("B", [|3.0f; 4.0f|]); ("A", [|2.0f|]) |]
Now I need a new array:
let sumA = [| ("A", [|1.0f; 2.0f|]); ("B", [|1.0f; 2.0f; 3.0f; 4.0f|]); ("C", [|1.0f; 2.0f; 3.0f; 4.0f; 5.0f|]) |]
For a1 and a2, if the first element of the tuple is the same, then concat the second element of array to get the new tuple.
Anyone who can solve this, please show me your code!
Thanks and have a nice week end!

.

for example smth like this:

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let a1 = [| ("A", [|1.0f|]); ("B", [|1.0f; 2.0f|]); ("C", [|1.0f; 2.0f; 3.0f|]) |]
let a2 = [| ("C", [|4.0f; 5.0f|]); ("B", [|3.0f; 4.0f|]); ("A", [|2.0f|]) |]

let f a b = 
    let lookup = 
        b  |> dict

    a
    |> Array.map (fun ((k1, v1) as kv1) ->
        match lookup.TryGetValue k1 with
        | true, v2 -> k1, Array.append v1 v2
        | false, _ -> kv1
        )


let sumA = [| ("A", [|1.0f; 2.0f|]); ("B", [|1.0f; 2.0f; 3.0f; 4.0f|]); ("C", [|1.0f; 2.0f; 3.0f; 4.0f; 5.0f|]) |]

let sumB = f a1 a2
printfn "%b" (sumA = sumB) // true
By on 12/18/2010 1:57 AM ()

Thank you very much!
Your code works!
Have a nice weekend!

By on 12/18/2010 3:09 AM ()

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