Computes the absolute value of vector elements.

Syntax

IppStatus ippsAbs_32f_A24 (const Ipp32f* pSrc, Ipp32f* pDst, Ipp32s len);

IppStatus ippsAbs_64f_A53 (const Ipp64f* pSrc, Ipp64f* pDst, Ipp32s len);

IppStatus ippsAbs_32fc_A11 (const Ipp32fc* pSrc, Ipp32f* pDst, Ipp32s len);

IppStatus ippsAbs_32fc_A21 (const Ipp32fc* pSrc, Ipp32f* pDst, Ipp32s len);

IppStatus ippsAbs_32fc_A24 (const Ipp32fc* pSrc, Ipp32f* pDst, Ipp32s len);

IppStatus ippsAbs_64fc_A26 (const Ipp64fc* pSrc, Ipp64f* pDst, Ipp32s len);

IppStatus ippsAbs_64fc_A50 (const Ipp64fc* pSrc, Ipp64f* pDst, Ipp32s len);

IppStatus ippsAbs_64fc_A53 (const Ipp64fc* pSrc, Ipp64f* pDst, Ipp32s len);

Include Files

ippvm.h

Domain Dependencies

Headers: ippcore.h

Libraries: ippcore.lib

Parameters

pSrc

Pointer to the source vector.

pDst

Pointer to the destination vector.

len

Number of elements in the vectors.

Description

This function computes the absolute value of the vector pSrc elements and stores the result in the corresponding element of the vector pDst.

For single precision data:

function flavor ippsAbs_32fc_A11 guarantees 11 correctly rounded bits of significand, or at least 3 exact decimal digits;

function flavor ippsAbs_32fc_A21 guarantees 21 correctly rounded bits of significand, or 4 ulps, or about 6 exact decimal digits;

function flavors ippsAbs_32f_A24 and ippsAbs_32fc_A24 guarantee 24 correctly rounded bits of significand, including the implied bit, with the maximum guaranteed error within 1 ulp.

For double precision data:

function flavor ippsAbs_64fc_A26 guarantees 26 correctly rounded bits of significand, or 6.7E+7 ulps, or approximately 8 exact decimal digits;

function flavor ippsAbs_64fc_A50 guarantees 50 correctly rounded bits of significand, or 4 ulps, or approximately 15 exact decimal digits;

function flavors ippsAbs_64f_A53 and ippsAbs_64fc_A53 guarantee 53 correctly rounded bits of significand, including the implied bit, with the maximum guaranteed error within 1 ulp.

The computation is performed as follows:

pDst[n] = |pSrc1[n]|, 0 ≤ n < len.

Return Values

ippStsNoErr

Indicates no error.

ippStsNullPtrErr

Indicates an error when pSrc1, pSrc2 or pDst 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 ippsAbs.

IppStatus ippsAbs_32fc_A24_sample(void)
{
const Ipp32fc x[2] = {{+2.885,-1.809}, {-0.543,-2.809}};
Ipp32fc  y[2];
   IppStatus st = ippsAbs_32fc_A24( x, y, 2 );
    printf(" ippsAbs_32fc_A24:\n"); 
     printf(" x = %+.3f%+.3f*i   %+.3f%+.3f*i \n", x[0].re, x[0].im, x[1].re, x[1].im);
   printf(" y = %+.3f          %+.3f%       \n", y[0],             y[1]);
       return st;
}
Output results:
 ippsAbs_32fc_A24:
  x = +2.885-1.809*i   -0.543-2.809*i
  y = +3.405           +2.861
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