---
title: vDSP_normalize
framework: accelerate
role: symbol
role_heading: Function
path: accelerate/vdsp_normalize
---

# vDSP_normalize

Computes single-precision mean and standard deviation, and then calculates new elements to have a zero mean and a unit standard deviation.

## Declaration

```occ
extern void vDSP_normalize(const float *__A, vDSP_Stride __IA, float *__C, vDSP_Stride __IC, float *__Mean, float *__StandardDeviation, vDSP_Length __N);
```

## Parameters

- `__A`: Single-precision input vector.
- `__IA`: Stride for A.
- `__C`: Single-precision output vector, or NULL (see Discussion below).
- `__IC`: Stride for C.
- `__Mean`: Single-precision mean of the elements of A.
- `__StandardDeviation`: Single-precision standard deviation of the elements of A.
- `__N`: Number of elements in A.

## Discussion

Discussion The function calculates values for Mean and StandardDeviation, then calculates new values for A to have a zero mean and unit standard deviation. For iOS 9.0 and later or macOS 10.11 and later, the production of new elements may be omitted by passing NULL for C. In this case A remains unchanged.

## See Also

### Normalization Functions

- [Finding the sharpest image in a sequence of captured images](accelerate/finding-the-sharpest-image-in-a-sequence-of-captured-images.md)
- [vDSP_normalizeD](accelerate/vdsp_normalized.md)