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# multiply(addition:_:)

Returns the single-precision element-wise product of the sum of two vectors and a scalar value.

```
static func multiply<T, U>(addition: (a: T, b: U), _ scalar: Float) -> [Float] where T : AccelerateBuffer, U : AccelerateBuffer, T.Element == Float, U.Element == Float
```

## Parameters

`addition`

A tuple that contains the vectors `A` and `B` in `D = (A + B) * C`.

`scalar`

The input scalar value `C` in `D = (A + B) * C`.

## Return Value

The output vector `D` in `D = (A + B) * C`.

## Discussion

This function calculates the element-wise sum of vectors `A` and `B`, multiplies the sum by scalar value `C`, and writes the result to vector `D`.

```swift
 for (n = 0; n < N; ++n)
    D[n] = (A[n] + B[n]) * C;
```

![A diagram showing the operation of this function. There are four rows. The top row represents the input vectors, A and B, with three boxes of each. The second row represents the operation that adds A to B, with three boxes, as well as the input scalar C with one box. The third row represents the multiplication operation as three boxes. The bottom row represents the output vector D as three boxes. The diagram has connecting lines from the input vectors to the operations, and from the operations to the output vector. ](images/com.apple.accelerate/media-4383301@2x.png)

The following code shows an example of using this function:

```swift
    let a: [Float] = [ 1,  2,  3,  4,  5]
    let b: [Float] = [10, 20, 30, 40, 50]
    let c: Float = 5
    
    let d = vDSP.multiply(addition: (a, b),
                          c)
    
    // Prints "[55.0, 110.0, 165.0, 220.0, 275.0]".
    print(d)
```

---

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