CMSIS-DSP  Version 1.8.0
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Complex-by-Real Multiplication

Functions

void arm_cmplx_mult_real_f32 (const float32_t *pSrcCmplx, const float32_t *pSrcReal, float32_t *pCmplxDst, uint32_t numSamples)
 Floating-point complex-by-real multiplication. More...
 
void arm_cmplx_mult_real_q15 (const q15_t *pSrcCmplx, const q15_t *pSrcReal, q15_t *pCmplxDst, uint32_t numSamples)
 Q15 complex-by-real multiplication. More...
 
void arm_cmplx_mult_real_q31 (const q31_t *pSrcCmplx, const q31_t *pSrcReal, q31_t *pCmplxDst, uint32_t numSamples)
 Q31 complex-by-real multiplication. More...
 

Description

Multiplies a complex vector by a real vector and generates a complex result. The data in the complex arrays is stored in an interleaved fashion (real, imag, real, imag, ...). The parameter numSamples represents the number of complex samples processed. The complex arrays have a total of 2*numSamples real values while the real array has a total of numSamples real values.

The underlying algorithm is used:

for (n = 0; n < numSamples; n++) {
    pCmplxDst[(2*n)+0] = pSrcCmplx[(2*n)+0] * pSrcReal[n];
    pCmplxDst[(2*n)+1] = pSrcCmplx[(2*n)+1] * pSrcReal[n];
}

There are separate functions for floating-point, Q15, and Q31 data types.

Function Documentation

void arm_cmplx_mult_real_f32 ( const float32_t pSrcCmplx,
const float32_t pSrcReal,
float32_t pCmplxDst,
uint32_t  numSamples 
)
Parameters
[in]pSrcCmplxpoints to complex input vector
[in]pSrcRealpoints to real input vector
[out]pCmplxDstpoints to complex output vector
[in]numSamplesnumber of samples in each vector
Returns
none
void arm_cmplx_mult_real_q15 ( const q15_t pSrcCmplx,
const q15_t pSrcReal,
q15_t pCmplxDst,
uint32_t  numSamples 
)
Parameters
[in]pSrcCmplxpoints to complex input vector
[in]pSrcRealpoints to real input vector
[out]pCmplxDstpoints to complex output vector
[in]numSamplesnumber of samples in each vector
Returns
none
Scaling and Overflow Behavior
The function uses saturating arithmetic. Results outside of the allowable Q15 range [0x8000 0x7FFF] are saturated.
void arm_cmplx_mult_real_q31 ( const q31_t pSrcCmplx,
const q31_t pSrcReal,
q31_t pCmplxDst,
uint32_t  numSamples 
)
Parameters
[in]pSrcCmplxpoints to complex input vector
[in]pSrcRealpoints to real input vector
[out]pCmplxDstpoints to complex output vector
[in]numSamplesnumber of samples in each vector
Returns
none
Scaling and Overflow Behavior
The function uses saturating arithmetic. Results outside of the allowable Q31 range[0x80000000 0x7FFFFFFF] are saturated.