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# vDSP_vrsum

Performs running sum integration over a single-precision vector.

```
extern void vDSP_vrsum(const float *__A, vDSP_Stride __IA, const float *__S, float *__C, vDSP_Stride __IC, vDSP_Length __N);
```

## Parameters

`__A`

Single-precision real input vector.

`__IA`

Address stride for `A`.

`__S`

Points to single-precision real input scalar: weighting factor.

`__C`

Single-precision real output vector.

`__IC`

Stride for `C`

`__N`

The number of elements to process.

## Discussion

Performs the following operation:

![mathematical formula](images/com.apple.accelerate/media-2557738@2x.png)

Integrates vector `A` using a running sum from vector `C`. Vector `A` is weighted by scalar `*S` and added to the previous output point. The first element  from vector `A` is not used in the sum.

---

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