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# vDSP_vadd

Calculates the single-precision element-wise sum of two vectors, using the specified stride.

```
extern void vDSP_vadd(const float *__A, vDSP_Stride __IA, const float *__B, vDSP_Stride __IB, float *__C, vDSP_Stride __IC, vDSP_Length __N);
```

## Parameters

`__A`

The first input vector, `A`.

`__IA`

The distance between the elements in the first input vector.

`__B`

The second input vector, `B`.

`__IB`

The distance between the elements in the second input vector.

`__C`

The output vector, `C`.

`__IC`

The distance between the elements in the output vector.

`__N`

The number of elements that the function processes.

## Discussion

This function calculates the sums of the first `N` elements of input vectors `A` and `B`, and writes the result to output vector `C`.

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

![A diagram showing the operation of this function. There are three rows. The top row represents the input vectors, A and B, with three boxes of each. The middle row represents the operation as three boxes with plus signs. The bottom row represents the output vector C as three boxes. The diagram has connecting lines from the input vectors to the operation, and from the operation to the output vectors.](images/com.apple.accelerate/media-4389091@2x.png)

The following code shows an example of using this function:

```swift
    let stride = 1
    let count = 5

    let a: [Float] = [ 1,  2,  3,  4,  5]
    let b: [Float] = [10, 20, 30, 40, 50]

    let c = [Float](unsafeUninitializedCapacity: count) {
        buffer, initializedCount in
        
        vDSP_vadd(a, stride,
                  b, stride,
                  buffer.baseAddress!, stride,
                  vDSP_Length(count))
        
        initializedCount = count
    }
   
    // Prints "[11.0, 22.0, 33.0, 44.0, 55.0]".
    print(c)
```

---

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