Intel® Integrated Performance Primitives (Intel® IPP) Developer Guide and Reference

ID 790148
Date 3/22/2024
Public
Document Table of Contents

Mean

Computes the mean value of a vector.

Syntax

IppStatus ippsMean_32f(const Ipp32f* pSrc, int len, Ipp32f* pMean, IppHintAlgorithm hint);

IppStatus ippsMean_32fc(const Ipp32fc* pSrc, int len, Ipp32fc* pMean, IppHintAlgorithm hint);

IppStatus ippsMean_64f(const Ipp64f* pSrc, int len, Ipp64f* pMean);

IppStatus ippsMean_64fc(const Ipp64fc* pSrc, int len, Ipp64fc* pMean);

IppStatus ippsMean_16s_Sfs(const Ipp16s* pSrc, int len, Ipp16s* pMean, int scaleFactor);

IppStatus ippsMean_32s_Sfs(const Ipp32s* pSrc,int len,Ipp32s* pMean,int scaleFactor);

IppStatus ippsMean_16sc_Sfs(const Ipp16sc* pSrc, int len, Ipp16sc* pMean, int scaleFactor);

Include Files

ipps.h

Domain Dependencies

Headers: ippcore.h, ippvm.h

Libraries: ippcore.lib, ippvm.lib

Parameters

pSrc

Pointer to the source vector.

pMean

Pointer to the output result.

len

Number of elements in the vector

hint

Suggests using specific code. The possible values for the hint argument are described in Hint Arguments.

scaleFactor

Scale factor, refer to Integer Scaling.

Description

This function computes the mean (average) of the vector pSrc, and stores the result in pMean. The mean of pSrc is defined by the formula:



The hint argument suggests using specific code, either faster but less accurate calculation, or more accurate but slower calculation.

Return Values

ippStsNoErr

Indicates no error.

ippStsNullPtrErr

Indicates an error when the pMean or pSrc pointer is NULL.

ippStsSizeErr

Indicates an error when len is less than or equal to 0.

Example

The example below shows how to use the function ippsMean_32f

void mean(void) {
      Ipp32f *x = ippsMalloc_32f(1000), mean;
      int i;
      for(i = 0; i<1000; ++i) x[i] = (float)rand() / RAND_MAX;
      ippsMean_32f(x, 1000, &mean, ippAlgHintFast);
      printf_32f("mean =", &mean, 1, ippStsNoErr);
      ippsFree(x);
}

Output:

 mean = 0.492591
Matlab* Analog: 
    >> x = rand(1,1000); mean(x)