Developer Reference

  • 2020
  • 07/15/2020
  • Public Content
Contents

Threshold_LTInv

Computes the inverse of vector elements after limiting their magnitudes by the given lower bound.

Syntax

IppStatus ippsThreshold_LTInv_32f(const Ipp32f*
pSrc
, Ipp32f*
pDst
, int
len
, Ipp32f
level
);
IppStatus ippsThreshold_LTInv_64f(const Ipp64f*
pSrc
, Ipp64f*
pDst
, int
len
, Ipp64f
level
);
IppStatus ippsThreshold_LTInv_32fc(const Ipp32fc*
pSrc
, Ipp32fc*
pDst
, int
len
, Ipp32f
level
);
IppStatus ippsThreshold_LTInv_64fc(const Ipp64fc*
pSrc
, Ipp64fc*
pDst
, int
len
, Ipp64f
level
);
IppStatus ippsThreshold_LTInv_32f_I(Ipp32f*
pSrcDst
, int
len
, Ipp32f
level
);
IppStatus ippsThreshold_LTInv_64f_I(Ipp64f*
pSrcDst
, int
len
, Ipp64f
level
);
IppStatus ippsThreshold_LTInv_32fc_I(Ipp32fc*
pSrcDst
, int
len
, Ipp32f
level
);
IppStatus ippsThreshold_LTInv_64fc_I(Ipp64fc*
pSrcDst
, int
len
, Ipp64f
level
);
Include Files
ipps.h
Domain Dependencies
Headers:
ippcore.h
,
ippvm.h
Libraries:
ippcore.lib
,
ippvm.lib
Parameters
pSrc
Pointer to the source vector.
pDst
Pointer to the destination vector.
pSrcDst
Pointer to the source and destination vector for the in-place operation.
len
Number of elements in the vector.
level
Value used to limit each element of
pSrc
or
pSrcDst
.This argument must always be real and positive.
Description
This function computes the inverse of elements of the vector
pSrc
and stores the result in
pDst
. The computation occurs after first limiting the magnitude of each element by the threshold value
level
.
The in-place flavors of
ippsThreshold_LTInv
compute the inverse of elements of the vector
pSrcDst
and store the result in
pSrcDst
. The computation occurs after first limiting the magnitude of each element by the threshold value
level
.
The threshold operation is performed to avoid division by zero. Since
level
represents a magnitude, it is always real and must be positive. The formula for
ippsThreshold_LTInv
is the following:
If the function encounters zero-valued vector elements and
level
is also 0 (see appendix A "Handling of Special Cases" ), the output value is set to
Inf
(infinity), but operation execution is not aborted:
Return Values
ippStsNoErr
Indicates no error.
ippStsNullPtrErr
Indicates an error when the
pSrc
,
pDst
, or
pSrcDst
pointer is
NULL
.
ippStsSizeErr
Indicates an error when
len
is less than or equal to zero.
ippStsThreshNegLevelErr
Indicates an error when
level
is negative.
ippStsInvZero
Indicates a warning when
level
and a vector element are equal to zero. Operation execution is not aborted. The value of the destination vector element is
Inf
.

Example

Threshold_LtInv
:
/******************************************************************************* * Copyright 2015-2020 Intel Corporation. * * This software and the related documents are Intel copyrighted materials, and * your use of them is governed by the express license under which they were * provided to you (License). Unless the License provides otherwise, you may not * use, modify, copy, publish, distribute, disclose or transmit this software or * the related documents without Intel's prior written permission. * * This software and the related documents are provided as is, with no express * or implied warranties, other than those that are expressly stated in the * License. *******************************************************************************/ #include <stdio.h> #include "ipp.h" /* Next two defines are created to simplify code reading and understanding */ #define EXIT_MAIN exitLine: /* Label for Exit */ #define check_sts(st) if((st) != ippStsNoErr) goto exitLine; /* Go to Exit if Intel(R) Integrated Primitives (Intel(R) IPP) function returned status different from ippStsNoErr */ /* Results of ippMalloc() are not validated because Intel(R) IPP functions perform bad arguments check and will return an appropriate status */ int main() { Ipp32f pVals[] = { 1, 3, 5, 7, 18, 24, 35, 48 }; Ipp32f pOutVals[8]; IppStatus status; int i; printf("Source vector\n"); for (i = 0; i < 8; i++) printf("%f ", pVals[i]); check_sts(status = ippsThreshold_LTInv_32f(pVals, pOutVals, 8, 2)); printf("Result values vector\n"); for (i = 0; i < 8; i++) printf("%f ", pOutVals[i]); EXIT_MAIN printf("Exit status %d (%s)\n", (int)status, ippGetStatusString(status)); return (int)status; }
Threshold_LtInv_I
:
/******************************************************************************* * Copyright 2015-2020 Intel Corporation. * * This software and the related documents are Intel copyrighted materials, and * your use of them is governed by the express license under which they were * provided to you (License). Unless the License provides otherwise, you may not * use, modify, copy, publish, distribute, disclose or transmit this software or * the related documents without Intel's prior written permission. * * This software and the related documents are provided as is, with no express * or implied warranties, other than those that are expressly stated in the * License. *******************************************************************************/ #include <stdio.h> #include "ipp.h" /* Next two defines are created to simplify code reading and understanding */ #define EXIT_MAIN exitLine: /* Label for Exit */ #define check_sts(st) if((st) != ippStsNoErr) goto exitLine; /* Go to Exit if Intel(R) Integrated Primitives (Intel(R) IPP) function returned status different from ippStsNoErr */ /* Results of ippMalloc() are not validated because Intel(R) IPP functions perform bad arguments check and will return an appropriate status */ int main() { Ipp32f pVals[] = { 1, 3, 5, 7, 18, 24, 35, 48 }; IppStatus status; int i; printf("Source vector\n"); for (i = 0; i < 8; i++) printf("%f ", pVals[i]); check_sts(status = ippsThreshold_LTInv_32f_I(pVals, 8, 2)); printf("Result values vector\n"); for (i = 0; i < 8; i++) printf("%f ", pVals[i]); EXIT_MAIN printf("Exit status %d (%s)\n", (int)status, ippGetStatusString(status)); return (int)status; }

Product and Performance Information

1

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Notice revision #20110804