# add(multiplication:_:) Returns the double-precision element-wise addition of the product of a vector and a scalar value, and a vector. ``` static func add(multiplication: (a: U, b: Double), _ scalar: Double) -> [Double] where U : AccelerateBuffer, U.Element == Double ``` ## Parameters `multiplication` A tuple that contains the vector `A` and the scalar value `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 product of vector `A` and scalar value `B`, adds scalar value `C` to the product, and writes the result to vector `D`. ```swift for (n = 0; n < N; ++n) D[n] = A[n] * B + C[n]; ``` ![A diagram showing the operation of this function. There are four rows. The top row represents the input vector A with three boxes, and the scalar value B with one box. The second row represents the operation that multiplies A and B, with three boxes, as well as the input vector C with three boxes. The third row represents the addition 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-4387652@2x.png) The following code shows an example of using this function: ```swift let a: [Double] = [ 1, 2, 3, 4, 5] let b: Double = 10 let c: Double = 5 let d = vDSP.add(multiplication: (a, b), c) // Prints "[15.0, 25.0, 35.0, 45.0, 55.0]". print(d) ``` --- Copyright © 2026 Apple Inc. All rights reserved. | [Terms of Use](https://www.apple.com/legal/internet-services/terms/site.html) | [Privacy Policy](https://www.apple.com/privacy/privacy-policy)